Easy knockdown
Fill your meter, then press R + L + A or B to knockdown your opponent regardless of whether he is blocking.

Easy training
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.

Easy Training 2 (No pressing any buttons)
Go to the options screen and choose controller configeration. Once in there, press right and that should turn the auto blocking thing on. Exit options and go to your match. Pick training and pick "defense"
Then start the practice round by pressing "A".
After that you dont have to press any buttons until the full 30 seconds are done.

Big Glove Mode
During game play pause the game and press the yellow C buttons in this order:
up, down, up, up, down. you should hear the bell ring five times to confirm that you've activated this mode. Repeat these exact steps to de-activate.

Big Heads
While playing press start and use the c buttons left right left left right. You should hear the bell go off.