Instructions
Insert a USB flash drive into your computer. Create a folder named "PS3" on the flash drive. Create a folder named "THEME" inside the PS3 folder.
Download the Secret of Mana theme from the PlayStation Universe website (see Resources) and place it into the "THEME" folder on the USB flash drive.
Turn on the PlayStation 3 and insert the USB flash drive into one of the USB ports on the front of the console.
Scroll to the "Settings" section of the PlayStation 3 main menu and select "Theme Settings."
Select "Theme" to access the installed themes list. Scroll to the top of the list and select "Install." Select the name of the USB flash drive that you inserted, then highlight "SoM" and press the "X" button to install the Secret of Mana theme.
Select "Theme" to access the installed theme list. Highlight the "Secret of Mana" theme and press the "X" button to open the theme sub-menu. Select "Apply" to designate Secret of Mana as the current theme.