To Restore Magicka:
1) While in the game, hit (B) to bring up the menus.
2) Use the (L) and (R) triggers to switch to the Stats menu.
3) Used the D-pad to select the Magicka entry.
4) Press (BLACK) (WHITE) (WHITE) (BLACK) (WHITE)
5) Press and hold (A) until the desired Magicka level is reached.