Unlimited player attributes
Highlight one of the attributes on the player edit screen, then press L1, L2, X, Square, X. Then any or all attributes may be raised to 99.
Editable bankroll (North American version)
At the team edit screen, press Square, X, Square, L2, L1. Now highlight the money total and press Left or Right to change the total. Note: To accumulate unlimited money easily, press Left until the total passes below zero.
Control ball physics (PAL version)
At the team edit screen, press Square, X, Square, L2, L1.
At the team selection screen, quickly press R1, L1, Down, Up, Left.
Pause the game and press Square, Triangle, X, Square, Triangle(2), X(2), Square(6), Triangle(5) at the options screen.