make it look umm cool xD colors is ur choice try to make it look crazy like but not to much :O ill give 20k for it gl and have fun :P also if u can make it more like umm cartonish :P

it should be 512x512
refferences :

http://t0.gstatic.com/images?q=tbn:A...c9Jnj-Rrv9-V5A

http://t1.gstatic.com/images?q=tbn:A...sK78RotYHTTB3w