Gimp is a useless program if you want to create something. Using stupid stamps or whatever doesn't count. Just use Paint.NET and look on Google for some references.
Photofiltre mostly, I get down to paint.net transparency stuff
I use photofiltre for transparency too, too bad it's hard to understand the weird placement of transparent gradients in the menu.
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The Photofiltre glitch where you get errors because you've selected a place and tried to make a gradient there, following in some weird French error which disallows you to move your mouse to the middle of the screen is really annoying yea..