New Game -

When you beat the game watch through the ending/credits and when the word "Fin" pops up hit A and you will be prompted to save. When you save there will now be a star to the right of the file. Reload the file you will start a new game with all your equipment/characters/levels and if you had any blue hearts for characters they will turn back to red.

A bonus area will also be unlocked north of where you start off.