Just remember that you may not be in range of a VOR if you're on the ground (e.g. my home airfield has no beacons within 20 miles). When you select the frequency, be sure you get a good ident (morse beeps) for the beacon. No ident means you can't use the signal, so you will have to sort it out when you're airborne.
Note also that most VOR indicators fitted in small aircraft have a warning flag. When you switch on the nav kit, the warning flag goes away unless there's a problem (no power, no signal etc). So the simplest check could just be 'VOR on, no flags displayed'