How to delete all content on my Apple iPhone 6S (factory reset)
This option lets you erase all content and settings from the Apple iPhone 6S. The phone will be reset to the factory settings.
Warning: all media, data and settings will be erased. This action cannot be undone.
1. Touch Settings.
2. Scroll to and touch General.
3. Scroll to and touch Reset.
4. Touch Erase All Content and Settings.
5. Touch Erase iPhone.
6. Touch Erase iPhone.
7. The phone will reboot.