Maybe a dumbass question, but after many trips to rally sites have noticed that on those occasions the organisers have put small signs on lamposts, to guide peeps in further. It has worked in the past, as sometimes in rural areas ya tend to get a bit lost!!
A simple AR08 and an arrow would suffice
Just an idea, maybe potty. but it has helped marvellously in the past, its less embarrassing than ringing your mate to come find you