How to restore the factory settings of vivoz3?

Brief introduction to factory reset or double clearing:

Restore all settings: restore all settings in the system to the factory state, such as alarm clock, wallpaper, network settings, ringtones, etc. However, the media files in the phone will not be deleted.

Clear all data: All internal data (except SD card data) will be cleared, including downloaded software, contacts, SMS, etc.

Note: Please back up important data before this operation. You can click on the webpage link for graphic introduction.