From the Home screen, drag down the Notification panel.
Tap the Settings icon.
Scroll to System.
Tap System.
Scroll to Reset options.
Tap Reset options.
Before you proceed, make sure to back up all photos, videos, and data you'd like to keep. When you factory reset your device, all your files will be deleted.
Tap Erase all data (factory reset).
Tap RESET PHONE.
Tap ERASE EVERYTHING.
You've completed the steps!
