Here is my first tutorial for GIMP. Sorry, it's a little big, it's really simple and only covers 5 steps. I hope you like it, if theres any problems, i'll edit it. I'd like to see some of the results!
If theres any problems with tools used, or any other problems, e.g. it's unclear, i'll edit the tutorial. Post results please :D
EDIT: I have been told that my tutorial is unclear, and have been prompted to explain some stuff, Ha. So here goes:
What are C4D'S? C4D'S are images made in the program cinema 4D to add effects to Signatures. It's imporatant to have a few as you can get some really nice ones that give good effects.
How do I colourize a sig? In the toolbar at the very top of Gimp, click on Tools>Colour Tools>Colourize.
When in the colourize bit, pick a colour and set the saturation and brightness. Saturation is how much colour it has in it. If you make the sig red, and put saturation at it's highest, the sig will be bright red.
Brightness is obviously how bright the colour in the sig is. If you lower the brightness the colour will be darker [DUH] And if you leave it high it will be bright.
Is the scale tool important? The scale tool is important as it helps you scale your render down to a suitable size for making a sig. It's useful if your render is MASSIVE.
So where is the scale tool? The scale tool is the small pink box above the gradient tool on the Gimp toolbar.
Why is the Opacity important? Lowering the opacity of a render helps make it look likes it's blended better. Lowering the opacity also helps prevent the render looking a lot brighter than the rest of the sig.
You can find the opacity tool on the layers window, where you can lower the opacity. Click on the layers tab in the toolbar in the top of gimp.
Text and Borders. Text is simple, just pick where you want it and put your text there. To make a border, you have to merge all your layers into one. Right click on the sig, click layer, then keep clicking merge down until you have one layer. Then click on select, and press all. Pick the colour you want to be the colour of teh border, and then go to edit>stroke selection.
Set the stroke between 1px-3px. You don't one tooo big.
Okay. Hope everyone understands it now.
Well i'm guessing you mean how to download the brushes into GIMP. When you have downloaded them off Deviantart, save them to somewhere you can locate them easily. Copy and paste them all to the brushes file in the gimp 2.2 folder. Then reload gimp and they will all be in your brushes. :D