I normally use Photoshop and/or GIMP for creating user interface layouts, but a few years ago, I hadn't really done anything artistic with it. Here was my first effort a few years back to celebrate a fantasy baseball dynasty league win:
As you can see, it's all blue except for a lightning bolt and a few flares I created, but I sucked at clipping figures.
Just took a Barcelona jersey and manipulated it to get a good feel for the effects.
Then, I just took off from there:
I don't make sigs very often, which doesn't inspire too much faith in my work, but art is subjective and so, if I find it to be good, then that's all that matters.