Go to options and set the difficulty to one star, change the time to 30 seconds, the rounds to 1 and the damage level to the highest setting.
This is the best thing to do if you want to unlock all the costumes or get page 9.
Every character has a default set of 6 costumes. Pressing A, B, X, Y, L or R produces a different costume. However, each character has one hidden default costume. This can be accessed by pressing L + X + B (together) when picking your character.
Get three perfects and Q will challenge you after your 3 perfect.
Use the trick for Easy Arcade Mode to make life easier.