Things You'll Need
Instructions
Turn on your PS3 and plug a USB storage device, such as an external hard drive or flash drive, into one of the four USB ports on the rear of the PS3 console.
Use the directional pad on the PS3 controller to scroll to "System" in the main menu screen of the PS3 and press "X."
Scroll to "System settings" and press "X."
Scroll to "Backup utility" and press "X." You will then have the option to back up or restore data.
Select "Back up" and press "X." The system will then ask if you want to back up data to the hard disk of the system. Select "No" and press "X."
Select "USB device" as the destination and press "X." A status bar will appear on screen. When it finishes, the back up is complete.