1 Find "Call forwarding"
Slide two fingers down the display starting from the top edge of your phone.
Press Call forwarding.
2 Select divert type
The current settings are displayed.
Press one of the following options:
Forward when busy
Forward when unanswered
Forward when unreachable
3 Divert calls to voicemail
Key in +447836121121 and press ENABLE.
4 Return to the home screen
Press the home icon to return to the home screen.