Instructions
Change PS3 Controller Settings from the Cross Media Bar
Turn on your PlayStation 3 and PlayStation 3 controller.
Navigate to the "Settings" menu, then select the "Accessories" option.
Choose the "Reassign Controllers" option or the "Controller Vibration Function" option, whichever best suits your needs. Save any changes you have made.
Change PS3 Controller Layout While Playing a Game
Turn on your PS3 and PS3 controller.
Insert a PS3 game disc.
Navigate to the "Game" menu, and select the game you just inserted.
Begin playing a game, then press the "Start" button.
Navigate to the "Options" menu and select the "Controller Settings" or "Controller Layout" option. Customize the options to your own preferences.