How du u do fancy dribble moves nba 2k8 XBOX 360?

like streeetball ones but in a game. like i saw sum1 do it with iverson, like lift one knee up n dribble under it, and he also crouched and bounced it back and fourth for a few seconds behind his back, just flashy moves, cos i know theyre doable, check it on you youtube, "nuggets vs lakers 2k8" watch iverson, i want to know how to do that stuff. help anyone??