First I started with a small marker sketch using iPad proportions (below). I also blocked in some values with a gray marker. Simply planning ahead will make my Photoshop job easier.
Scan it. Open it in Photoshop. And starting painting in a layer right on top. Watch the nifty 2 minute screen recording below!
Check out the finished concept below.
The final vector illustration below. This is what it would look like in the game with the HUD and the Funny Fish and everything.