Hi Rob,
I have been a few times but not last year, if nothing has changed you will get a window sign with your tickets (only a few days before the show!), this will give instructions of how to get to your display area. If you have booked with the BMWCC code you will be with them (sorry us!). The event is huge but very well marshalled, once you get to the BMWCC area there is usually someone from BMWCC to direct you to a display area.
Park up, admire the other zeds (usually Z1s, 3s, 4s and 8s!) then go look at everything else (then realise 1 day isn't long enough to look at everything else!).
Make sure you are back in plenty of time for the parade lap, you have filled all your forms in and have got a wrist band. There is usually lots of waiting around for the parade lap, but worth it if it actually happens (got rained off last time I was there).
It is a great day out, looking forward to now.