You might want to improve the quality of your cards before you start offering to make them for people.
Best thing to start off with is using an actual Trainer Card background. You'll find all you need, including other sprites to use on The Spriter's Resource: http://sprites.fireball20xl.com/nintendo/index.html
You might want to also avoid using sprites and art together, especially when the art is squished in to fit messily.
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