HOW TO PROGRAM ONE TOUCH DIALING
You may assign any Direct Station Selection (DSS) button to an already existing DSS button for quick and easy dialing, as well as a visual indication of the busy/idle status of frequently called internal extension numbers.
From the phone to be programmed,
With the on-hook press [TRANSFER] and Dial 107
Press a One Touch Direct Station Selection button you want to program
Dial the extension number that you want to assign to this button.
Press [TRANSFER] to store you selection
How to program one-touch dialing