All dreamkeys
Pause the game in the house hub, then hold Select and press Circle, L1, L2, L1, L2.

All Winks
Pause the game in the house hub, then hold Select and press Left, Down, Right, Right, Right.

Full cogs
Pause the game at any place, then hold Select and press Down, R2, L1, Up, R2.

Reset lives
Pause the game at any place, then hold Select and press L1, Up, Right, L2, Up.

Reset moons
Pause the game at any place, then hold Select and press Up, L2, Left, R2, Left.

Reset Zzz's
Pause the game at any place, then hold Select and press Right, L1, Up, R1, L1.

Big head mode
Pause game play, then hold Select and press L1, Up, Right, L2, Up. Release Select. Then, hold Select again and press then press L1, Up, Right, L2, Up.