Take a look here! I found this sketch from Danger by Design:
Did you know that there have been a few different artists who created Sonny Joon's comical doodles? Sonny rocks, thanks to those talented artists behind the scenes!
I recommend taking a look at one of your favorite scenes, books, doodles, or any picture from inside a game that you enjoy looking at, and give it try! Try copying the style, the same way the colors flow and lines connect, add crazy captions like Sonny does, or design something like Minette or Heather McKay.
I feel like sketching now...