There are some serious roadworks around Nice airport at the moment, which means that there are temporary road signs in the area. We arrived via the A8 (the major motorway), coming from the West. The exit is marked as junction 51 from that direction. Once you are off the motorway beware - the signs are non-existant! I can't offer much more advice than this I'm afraid because we had to ask for directions and eventually overshot the entrance to the airport and finally found it approaching from the other direction. Needless to say, allow plenty of extra time before your flight!