To enable cheats, plug a second controller into port two on your Xbox and then take it out. Enter X, X, Y, Y, B, B, A, A on the first controller.
To unlock sepia graphics, enter the following combo with one controller plugged into the first port. After you’ve entered it, plug the second controller into the fourth port and take it out:
Left Trigger, Left Thumbstick, Right Thumbstick, A, B, Right Trigger, B, A, Right Thumbstick, Left Thumbstick, Left Trigger
To enable invincible mode, on the first controller enter X, Y, A, B, X, Y