While "option" is highlighted at the main menu, hold L1+L2+R1+R2 to display "secuirity clearence" screen, with a password entry prompt for the "invulnerable", "infinity ammo". "all missions" and "all bonuses" options. hold X and press D-pad to change one of the characters in the desired password. release X to input that character. press -> to highlight the next character and repeat until the password is filled. if you entered the code correctly, the text will turn orange. press to exit password entry screen.