1). With the power completely off, press and hold the VOLUME DOWN button.
2). With the Volume Down button still held, press the POWER BUTTON to turn on your device.
3). Once the device powers on, you may release the power button. Do NOT let go of the VOLUME DOWN button
4). Use VOLUME DOWN to go to RECOVERY and use the POWER BUTTON to select it.
5). Use VOLUME DOWN to go to WIPE DATA/FACTORY RESET and use the POWER BUTTON to select it.
6). Use VOLUME DOWN to go to YES - DELETE ALL USER DATA and use the POWER BUTTON to select it.
7). Once complete use the POWER BUTTON to choose REBOOT SYSTEM NOW.