The Texan-born playmaker is a part-time artist and insists his work is just as unpredictable as the way he plays the game.
Shea, 23, who joined the Potters in a £2.5million deal in January from MLS side FC Dallas, says his hobby keeps his mind at ease.
He told the Daily Star "I like to paint two or three times a week.
"If you look at my paintings you will see a lot of them are bold, bright and unpredictable.
"And I play my football in pretty much the same way - so there is a comparison.
"I don't know what I'm going to do out on the pitch. I just like to go out there and it happens - that is exactly the same with my paintings.
"I play my best when I don't think about things and just do things on the spur of the moment. I am a free spirit, I suppose.
"Football can be a very stressful game when things aren't going your way. Something like painting can really help to keep your mind at ease."