Find "Mobile networks"
Slide your finger down the display starting from the top edge of your phone.
Press the settings icon.
Press the settings icon.
Press More....
Press Mobile networks.
Turn mobile data on or off
Press Data enabled to turn the function on or off.
If you turn on mobile data:
Press OK to confirm.
Press OK to confirm.
Return to the home screen
Press the Home key to return to the home screen.