During the game, pause and press the following:
At the main menu (where you can choose 1 Player/2Players, enter the options, load your game, etc), press the following buttons. A sound should be heard if done correctly.
At the Options Menu #1, press the following buttons. A sound should be heard if done correctly. *Note: all the codes have to be entered in Option Menu #1, but they will appear in Option Menu #2.