From the Title Menu, choose Options. In the options menu, press Left, Right, R1, R2, L2, L1, Up, Down. A timer counting down from 30 seconds will appear. Highlight the Credits option and press the X button quickly and repeatedly. Your credits will build up quickly at first, but then they'll be harder to get as you accumulate more. you may receive up to 30 credits, depending on how quick you are.