Once you have set up your phone book in your Dashboard > Config > Phone Books, you will need to link it to your handset(s) by accessing the GUI (IP address) of each handset.

Once logged into the GUI, go to Phonebook > Phonebook Management, and fill in the details as per the screenshot below - the HTTP/HTTPS username, HTTP/HTTPS password and Server Path are all generated in the Yay.com Phonebook you created earlier!