No matter where you are on the court, crash the boards when your opponent throws up a shot. If their shot doesn't go in, jump high for the rebound and try to grab the ball at its highest point. The more bodies that you have under the basket, the better the chances that you'll get the rebound. There's nothing more embarrassing for the other team than having a shot swatted away by your big man in the middle. So when the offense is looking for the easy basket underneath, control your center and time your opponent's shot in order to deny the bucket.
Steals are another way to create a turnover.
Use the steal button when you're defending in front, or if you're coming up from behind. But be careful, the ref will blow his whistle if you're making too much contact. Passing is key when running the Motion offense. After passing the ball to an open player, look for teammates moving toward the basket. Keep passing until you find an open shot.