Big Head Mode -- Pause the game and press C-Left, C-Right, C-Left (x2), C-Right. If you entered the code correctly, you will hear the bell ring five times. Repeat the code to disable.
Big Gloves Mode -- Pause the game and press C-Up, C-Down, C-Up (x2), C-Down. If you entered the code correctly, you will hear the bell ring five times. Repeat the code to disable.
Fill your meter, then press R + L + A or B to knockdown your opponent regardless of whether he is blocking or not.
Select "Offense" in training mode. Then, use the following moves to hit the blue opponent: Down + A, Down + A, Down + B, Down + B. Repeat until he has been hit thirty times.
Press A + B + R and the direction to punch while the glove in the upper corner is flashing,
Move away from your opponent, hold Z and sweep the Analog-stick in circles. You can also try tapping Z repeatedly without moving the Analog-stick.