Find "Factory data reset"
Press Applications.
Press Settings.
Press Privacy.
Press Factory data reset.
Restore the factory default settings
Press Reset phone.
Press Erase everything.
Wait a moment while the phone restores the factory default settings.
Follow the instructions on the display to configure the phone and prepare it for use.
Wait a moment while the phone restores the factory default settings.
Follow the instructions on the display to configure the phone and prepare it for use.