I used this tutorial: http://www.gimptalk.com/forum/topic/Line-Abstract-Tut-11250-1.html here's my sig: I think it came out pretty good for a first try. CnC? I know the text is hard to read, sorry ^^;
Save your stuff as png not jpg. Better quality imo. I know it's hard adjusting to a new program so just keep trying :P
not bad for your first time, I wouldnt have used the color you chose for the text, I would have changed it to something more readable, but overall, pretty good for your first try.