Instructions
Connect your external hard drive to your computer and click the "Start" button on your computer task bar. Right-click "Computer" and click "Manage." Click "Disk Management."
Right-click your external hard drive and click "Format." Click the "File System" button and select "FAT32." Click "Quick Format" and "Start" to format the external hard drive into a readable PS3 format.
Right-click the external hard drive again and click "Eject" to safely disconnect it from your computer. Turn your PS3 on and connect it to your PS3. Your PS3 will read the drive and you will be able to save data to it.