(Level Select)
Up,Down,Left,Right then hold Square and press Start.
(Debug Mode)
Circle,Up,Circle,Down,Circle,Left,Circle,Right then hold Square and press Start.
In Gameplay press:
X to turn into a item.
Square to change item when an item.
Circle to drop item when an item.
When Gameplay is paused press:
X for slowmotion.
Square to reset game.
Circle to advance frame.
And while in debug mode Sonic is invincible.
P.S hope you like the cheats