The outside area is pretty simple, though it can be confusing because you can't see the whole place at once. There are two tents, one where people sleep (the residence tent) and one for restoration (the antiquities tent). In front of the residence tent is a large truck full of water and some chairs; this is where Dylan sits after he shows up.
In front of the antiquities tent there are a couple of tables with lighting equipment; you can't ever go there, so you can ignore it. The entrance to the tomb is the hole in the ground in front of the two tents.
The tomb is more complicated, so stop in the antiquities tent before you go in and pick up the map on the left-hand table. This map will update when you discover new tunnels, but it doesn't tell you where the puzzles are.
In general, the tomb consists of one main room and three tunnels that branch off of it. The three tunnels look a lot alike, so it's easy to get disoriented and repeatedly wander down the wrong tunnel, curse, and go back to try one of the other tunnels.