Just do what the title says, draw a pic of yourself and then put the two pics together and VOILA! you got yourself a twin!
Heres mine.
(I don't always look like this, it was just a pic from a clip of my cartoon thats in production)
Ahh, bless him . . . . . . . . . . . . . . . . . . . . . . . . . . . . OOOPS no he's dead,still looks happy