GwenRaiden
AKA Apology Girl
AKA a basic bitch guide to banner-making.
It's been like, over 2 years since I last used gimp, so I'm super rusty. Apologies for that. I still want to help people learn bits here and there, though. I made a super simple Cordy banner. I'll explain some of the steps along the way. It's only 2 images, 2 textures, and 2 fonts. The blending isn't great, and I didn't have time to mess about with the text the way I do in photoshop (gimp is far more complicated to use imo).
First of all, you can download gimp for free here.
Step 1
With gimp downloaded, go ahead and load it up. You'll get a page that looks like this. If you want to make a banner that fits the board rules here on BB, you will go File → New to create a new image. A dialogue box will pop up asking for an Image Size, like this. You want it to be 500 width and 150 height. Click OK. You now have your banner outline, see here.
Step 2
We are going to use two separate images of Charisma for the banner. This is the first one, so go ahead and save it on your computer (tip: you may want to create a folder for where you want all your arty bits to go so they're easier to find later). To open the Charisma image we will go File → Open as Layers, like so. Find your chosen image and click on Open (here). The Charisma image is MUCH bigger in size than our measly 500x150 banner outline, so we have to scale the image. You can do this by clicking on the Scale Tool found on the Toolbox (the thin panel on the left), have a look here if you can't find it. To scale your image, you want to drag down from the corners, but please please make sure the little link icon stays linked as you scale, otherwise your image be stretched and all out of whack! Click Scale to resize the image, then using the Move Tool (also found in the Toolbox panel, it looks like a four-pointed arrow) you can move your image into the banner box, continue to scale and move until you find a crop you're happy with. This is what I had. I repeated these steps with our second Charisma image (save the image to your art folder), only this time I turned the opacity down a bit to see better for where I wanted to place the second image. You'll find the opacity settings at the top of the Layers - Gradients panel located on the right of your gimp screen. So here's where we are.
Step 3
I put the opacity of the second Charisma image back up to 100%. So now we have our base. With the second Charisma image highlighted in the Layers Panel (the one that is covering most of the banner), I'm going to right-click and select Add Layer Mask, like so. Just go ahead and select White and click Add. A layer mask is a great way to blend images using brushes or gradients set to black/white. In simple terms, if you choose your layer mask to be white, black works as an eraser, erasing away whatever you don't want in the image. The good thing about layer masks is you can always go back and fix any mistakes by making your brush white again, and going over whatever you want to add back to the image. Click on the brush in the Toolbox panel and choose a soft brush like this. Now you want to lower the opacity of the brush and the brush size, you can see my settings here. With black selected as your active colour, and with your layer mask selected, you can start masking away the overlap in the images, like so, until you get the result you're happy with. Practice makes perfect when it comes to blending. You can be as precise or as "blendy" as you like, just remember to change your brush settings to full opacity, and maybe a sharper brush if you want to get in close to delete small details of your image.
Step 4
Next we're going to add a texture. This rose texture (save it to your computer/folder). We'll do that the same way as before, when we opened our Charisma images. It was File → Open as Layers, then find your texture in the folder you saved it to. I moved it around with the Move Tool until I was happy with where it was placed (tip: lower the opacity of textures when you're moving them around, so you can see how they will look later). With the rose texture layer highlighted, I lower the opacity to around 66%, I added a layer mask (right click → Add layer Mask → White) and using a soft black brush again, I masked away the parts I didn't want. Then, I inverted the rose texture by clicking Colours → Invert. This is how we look now.
Step 5
At this point I was just playing around with colouring. Looking at different ways to colour images using gimp. I'll try to give you a few examples in this step. You obviously don't have to use them all everytime you make a graphic. One way to colour is by using Curves. Colours → Curves. You'll see a graph and a line, you can add contrast and colour here by using points to create a curve. You can also change the value to red, green or blue. Here's a wee example of how they work.
Another way to colour your banner is by clicking Colours → Colour Balance, another dialogue box will pop up and here you can adjust either shadows, midtones or highlights by adjusting the colour levels below.
Duplicating your actual texture layers is another way to add more colours and brightness to your images (right click → Duplicate Layer) and setting that duplicated layer to a specific blend mode (or "mode", found in the Layers panel in a drop down menu like so). I duplicated the rose texture twice, setting it once to Screen and once to Soft Light. You can, as always, mess about the the opacity of these duplicate layers til you find something you like.
Using gradient maps to colour is one of my favourite methods but it seems quite limited on gimp. First of all, you want to create a New Layer from Visible. You can do this by clicking Layer → New from Visible. Next, you have to change your active foreground and background colours. You want to use colours that will compliment your image overall. You can do this by clicking on your foreground/background colours and using the eyedropper tool to select a colour already present in your image, then use the colour picker to make that colour more light/dark/vibrant. Once you've selected new foreground and background colours, you can select your gradient map. Colours → Map → Gradient Map. You'll end up with something like this. But by changing the blend mode to Soft Light, it turned into this. You could also try adding a new layer and adding a solid colour, again set to a different blend mode other than Normal, to get more specific colours into your graphic.
Step 6
I was happy with the colouring, blending and everything else, so at this point I right-clicked on my image and selected Flatten Image. Adding text is fairly easy. Click on the text tool in your Toolbox panel. Stretch out the space your want your text to be and type, like this. The options to change your text colours and size are all pretty easy to see and use. You can also duplicate your text layers (right-click on layer → Duplicate Layer) and change the text colour to create a different colour shadow for the same line of text, kinda like this. I wanted to add a bit more depth to the overall image so using this texture (savey save it and Open as Layers) I set it to Screen from the drop down Mode box, added a layer mask (right-click → Add Layer Mask) and using a black brush, this tome with opacity at 100%, I delete anything from the texture covering Charisma's face or the banner text. And that's it. To save your image you will click File → Export As → then select PNG or JPEG from the 'all export images' dropdown menu in the dialogue box, and give your file a name such as omgilearnedthisfromthatawfultutorialonbuffyboards.png.
Top tips: always save your work as you go. File → Save. I'd say every five minutes or so. Also, practice makes perfect, practice as much as possible to get used to all the tools and what they do. There's LOTS of guides and tutorials out there, and so much to learn when it comes to making graphics. Absorb as much of what is out there if you want to get to grasps with whatever program you are using. Set time aside to learn if it's something you really want to get into.
It's been like, over 2 years since I last used gimp, so I'm super rusty. Apologies for that. I still want to help people learn bits here and there, though. I made a super simple Cordy banner. I'll explain some of the steps along the way. It's only 2 images, 2 textures, and 2 fonts. The blending isn't great, and I didn't have time to mess about with the text the way I do in photoshop (gimp is far more complicated to use imo).

First of all, you can download gimp for free here.
Step 1
With gimp downloaded, go ahead and load it up. You'll get a page that looks like this. If you want to make a banner that fits the board rules here on BB, you will go File → New to create a new image. A dialogue box will pop up asking for an Image Size, like this. You want it to be 500 width and 150 height. Click OK. You now have your banner outline, see here.
Step 2
We are going to use two separate images of Charisma for the banner. This is the first one, so go ahead and save it on your computer (tip: you may want to create a folder for where you want all your arty bits to go so they're easier to find later). To open the Charisma image we will go File → Open as Layers, like so. Find your chosen image and click on Open (here). The Charisma image is MUCH bigger in size than our measly 500x150 banner outline, so we have to scale the image. You can do this by clicking on the Scale Tool found on the Toolbox (the thin panel on the left), have a look here if you can't find it. To scale your image, you want to drag down from the corners, but please please make sure the little link icon stays linked as you scale, otherwise your image be stretched and all out of whack! Click Scale to resize the image, then using the Move Tool (also found in the Toolbox panel, it looks like a four-pointed arrow) you can move your image into the banner box, continue to scale and move until you find a crop you're happy with. This is what I had. I repeated these steps with our second Charisma image (save the image to your art folder), only this time I turned the opacity down a bit to see better for where I wanted to place the second image. You'll find the opacity settings at the top of the Layers - Gradients panel located on the right of your gimp screen. So here's where we are.
Step 3
I put the opacity of the second Charisma image back up to 100%. So now we have our base. With the second Charisma image highlighted in the Layers Panel (the one that is covering most of the banner), I'm going to right-click and select Add Layer Mask, like so. Just go ahead and select White and click Add. A layer mask is a great way to blend images using brushes or gradients set to black/white. In simple terms, if you choose your layer mask to be white, black works as an eraser, erasing away whatever you don't want in the image. The good thing about layer masks is you can always go back and fix any mistakes by making your brush white again, and going over whatever you want to add back to the image. Click on the brush in the Toolbox panel and choose a soft brush like this. Now you want to lower the opacity of the brush and the brush size, you can see my settings here. With black selected as your active colour, and with your layer mask selected, you can start masking away the overlap in the images, like so, until you get the result you're happy with. Practice makes perfect when it comes to blending. You can be as precise or as "blendy" as you like, just remember to change your brush settings to full opacity, and maybe a sharper brush if you want to get in close to delete small details of your image.
Step 4
Next we're going to add a texture. This rose texture (save it to your computer/folder). We'll do that the same way as before, when we opened our Charisma images. It was File → Open as Layers, then find your texture in the folder you saved it to. I moved it around with the Move Tool until I was happy with where it was placed (tip: lower the opacity of textures when you're moving them around, so you can see how they will look later). With the rose texture layer highlighted, I lower the opacity to around 66%, I added a layer mask (right click → Add layer Mask → White) and using a soft black brush again, I masked away the parts I didn't want. Then, I inverted the rose texture by clicking Colours → Invert. This is how we look now.
Step 5
At this point I was just playing around with colouring. Looking at different ways to colour images using gimp. I'll try to give you a few examples in this step. You obviously don't have to use them all everytime you make a graphic. One way to colour is by using Curves. Colours → Curves. You'll see a graph and a line, you can add contrast and colour here by using points to create a curve. You can also change the value to red, green or blue. Here's a wee example of how they work.
Another way to colour your banner is by clicking Colours → Colour Balance, another dialogue box will pop up and here you can adjust either shadows, midtones or highlights by adjusting the colour levels below.
Duplicating your actual texture layers is another way to add more colours and brightness to your images (right click → Duplicate Layer) and setting that duplicated layer to a specific blend mode (or "mode", found in the Layers panel in a drop down menu like so). I duplicated the rose texture twice, setting it once to Screen and once to Soft Light. You can, as always, mess about the the opacity of these duplicate layers til you find something you like.
Using gradient maps to colour is one of my favourite methods but it seems quite limited on gimp. First of all, you want to create a New Layer from Visible. You can do this by clicking Layer → New from Visible. Next, you have to change your active foreground and background colours. You want to use colours that will compliment your image overall. You can do this by clicking on your foreground/background colours and using the eyedropper tool to select a colour already present in your image, then use the colour picker to make that colour more light/dark/vibrant. Once you've selected new foreground and background colours, you can select your gradient map. Colours → Map → Gradient Map. You'll end up with something like this. But by changing the blend mode to Soft Light, it turned into this. You could also try adding a new layer and adding a solid colour, again set to a different blend mode other than Normal, to get more specific colours into your graphic.
Step 6
I was happy with the colouring, blending and everything else, so at this point I right-clicked on my image and selected Flatten Image. Adding text is fairly easy. Click on the text tool in your Toolbox panel. Stretch out the space your want your text to be and type, like this. The options to change your text colours and size are all pretty easy to see and use. You can also duplicate your text layers (right-click on layer → Duplicate Layer) and change the text colour to create a different colour shadow for the same line of text, kinda like this. I wanted to add a bit more depth to the overall image so using this texture (savey save it and Open as Layers) I set it to Screen from the drop down Mode box, added a layer mask (right-click → Add Layer Mask) and using a black brush, this tome with opacity at 100%, I delete anything from the texture covering Charisma's face or the banner text. And that's it. To save your image you will click File → Export As → then select PNG or JPEG from the 'all export images' dropdown menu in the dialogue box, and give your file a name such as omgilearnedthisfromthatawfultutorialonbuffyboards.png.
Top tips: always save your work as you go. File → Save. I'd say every five minutes or so. Also, practice makes perfect, practice as much as possible to get used to all the tools and what they do. There's LOTS of guides and tutorials out there, and so much to learn when it comes to making graphics. Absorb as much of what is out there if you want to get to grasps with whatever program you are using. Set time aside to learn if it's something you really want to get into.