A couple of specific things to the fact that its an airfield -
They tend to be a lot more abrasive, so you will get loads of grip, so don't think you can corner just as fast when you get back on normal roads.
If you plan on driving home on your tyres afterwards, I would suggest putting a few more psi than normal in them to even the wear out across the tyre or you may find the inside/outside edges will be gone before you know it.
If you decide to play around a bit and get the tail out, again keep an eye out on your tyre wear for the above reason.
For some reason airfields seem to be particularly bad for lots of tiny little stones/grit that will pepper the front of your car, so don't be tempted to slipstream the car in front, unless your fancy a front end re-spray. If you keep your distance you'l be fine.
Due to the nature of an airfield being very open with wide runways and taxiways, its very hard to get an idea of speed and braking points (especially at the end of the runway) so bare that in mind.
Keep an eye on your fluids, but don't over fill them as they will get very hot (brakes and power steering) and end up spilling out all over your engine bay.
If you can, change your brake fluid before you go to something like Motul RBF600. There is nothing worse than getting to the end of the runway and wanting to slow down from 150+ mph and your brake peddle feels like jelly!
And most importantly, ENJOY it!!! There is no safer place to push your car to the limit, so you might as well find your limits there when all you can do is slide off onto the grass.