I know people will have the app that shows you where you are on site, and hopefully you'll get a paper map when you get there, but I think it is useful to have a few landmarks to know where you are on site especially for first-timers.
The site is in a valley that runs east to west with hills on the north and south sides. There are a couple of "main roads" in site that are concrete. Steanbow Farm Road runs south from Red Gate (marked in grey on the web map), the Pilton Bypass runs east from Red Gate up to Worthy Farm and on to VG2. Worthy Farm and VG2 are on the north hill and you'll also find all the helpful stuff like Welfare, Load and Found and the Medical Centre up there.
On the south side of the valley, running from Shangri La to Steanbow Farm Road is an old railway line that is a raised embankment which makes it easy to distinguish from the other mud tracks. On the north side of the valley are some electric pylons and power lines and these are a black line on the map, the blobs are the pylons.