The great thing about this game is that it gives you in-game advice whenever you need it. Just hit the Circle button for a Quick Hint move. For more detailed coaching, use the English Advice section in the main menu.
Control the center
In two-player matches, control the center of the board, castle your king early for protection, and always develop your pieces and promote your pawns.
Queen upgrade
When promoting your pawns, always choose the queen upgrade.
Quicker
If the single-player opponent is taking too long, push the Circle button to force him to make a move.
Watch movies
First things first; watch all of the movies in the Chess Rules option of the main menu to get the basics.