Instructions
Turn on the PS3 and allow the "XMB" display screen to load. Turn on the game controller.
Highlight the user account you wish to delete and press the game controller's "X" button to log in.
Highlight the user account again and press the "Triangle" button on the PS3 controller.
Scroll down to the "Delete" menu option and press the "X" button.
Press the "Right" button to highlight "Yes" and press the "X" button to confirm the deletion. Confirm the deletion once more by highlighting "Yes" and press the "X" button. After deleting the account, create a new account or login to an existing account to continue using the PS3.