1. Turn the power off
2. Press and hold the following keys at the same time:
Volume Down Key + Home Key + Power/Lock Key
3. Release all of the keys when you see the screen message "Permanently Erase User Data & Reset Settings".Press power key to confirm.
4. Press the Power/Lock key to confirm when pop-up message appear "Are you sure you want to continue to erase?"
5. Your phone will now be restored back to it's factory settings.