From the Home screen, tap Apps.
Swipe to Settings.
Tap Settings.
Tap ACCOUNTS.
Scroll to Backup and reset.
Tap Backup and reset. Before proceeding, make sure you designate a back up account. Otherwise, you will lose all photos, videos, and other information on your phone.
Tap Factory data reset.
Scroll to RESET DEVICE.
Tap RESET DEVICE.
Tap ERASE EVERYTHING.
You've completed the steps!
