1.    On the PS3 system XMB, go to the   (PlayStation Network). (Skip this step if you are already logged in.)

2.    Highlight   (Account Management) and press the   button.

3.    Highlight [Redeem Codes] and press the   button.

4.    Enter the code printed on the voucher or PlayStation Network Card. The funds or item will be added to your account.

Please not that the code is case sensitive. Be sure to enter the code exactly as it is printed. Using the on-screen keyboard?Learn How

5.    Once the voucher is entered, games will appear in the Download List.
Or go to the Sony Support page