Samsung Galaxy S III

Find "Voice call"

Press Apps.

Find "Voice call"

Press Phone.

Find "Voice call"

Press the Menu key.

Find "Voice call"

Press Call settings.

Find "Voice call"

Press Call forwarding.

Find "Voice call"

Press Voice call.

Select divert type

The current settings are displayed.

Select divert type

Press one of the following options:
Always forward

Select divert type

Forward when busy

Select divert type

Forward when unanswered

Select divert type

Forward when unreachable

Divert calls to voicemail

Key in (prefix) 5 (your phone number) and press Enable.

Exit

Press the Home key to return to standby mode.