I tend to use the system abbreviated dial feature "change abbreviated-dialing system". In here you can enter FAC/DAC's/SD's etc into the dial code section and then use the "Label for 2420/4620 Station" section to name the buttons. I use things such as login, logout,AUX codes etc.
You will also need to give the station access to the "System" Ab-dial.
The just programme the buttons to access
abrv-dial, List: x, DC: 01 etc etc