1.With the phone completely powered off, hold the power button and the volume up and volume down buttons simultaneously until the phone vibrates.
2.Using volume down, select "recovery mode" by using the volume up button to choose the selection.
3.When you see the Android logo, tap the "home" (middle soft button) button.
4.Scroll down and select "Wipe Data/Factory reset" using the left soft button to choose selection.
5.Next scroll down to "delete all user data" and use the left soft button to choose the selection.
6.Next, select "reboot now" again with the left soft button.