Begining the Hard reset, hold the Power key till you see the option to power off you device.
Upon device shut-off, hold Power key and Volume Up until you see the Recovery mode.
You should now see the Recovery mode, from this meny select "Wipe data/factory reset" using the Volume keys to navigate and confirm it with the Power key.
Affirm this once more by selecting "Yes" and wait for the device to remove all personal data.
