>>7685898GIMP is freeware that is as good as Photoshop, I feel.
I'd get rid of the few scratches/specs there with a clone tool.
However, I think this would look dope vectorized through another freeware program known as "Inkscape." Adobe Illustrator is the costly version of Inkscape.
All of these programs have in-depth tutorials on YouTube. If you get good enough at Inkscape, you can make money for yourself or others being able to make images from drawings/photos into printable shirts/mugs/etc. Heads up, 7up.
Pic-related. That's me meeting Royce Da 5'9" at St. Andrew's, Detroit wearing my Dilla shirt. I met him after his concert backstage in The Shelter for giving him a bunch of art. This is where many Detroit HipHopians became famous. It's also where the battlerap scenes are from "8-Mile." It was truly an honor.