Okay, so i know that when i first started out, the hardest thing to do for me, was make hair textures. I couldn't figure out how to do it. A lot of people think you need Photoshop to do it, but here is a quick way to do it with gimp(:
Note: This way doesn't work particularly good if you're starting out with dark hair.
Okay, so open Gimp2. And get your texture loaded:
And now, click on your path tool.
and start out lining the hair texture.
Once you finish, click "Select" at the top and then click "From Path"
Now select "air brush"
Say you wanted pink hair, so you choose your color.
Now, we make the size of the brush pretty big. I like to do somewhere around 546.
and Turn the Opacity down to about 75
and lightly airbrush the hair.
Finishing Product:
Hope this helped!(: