Jennifer.....Leveling can be complicated but it is not that much different to levalling a single axle van.
We find levelling "front to back" is difficult, particularly if you are on a steep incline because you are limited to adjustment on the jockey wheel. If you are going to a new site it is a good idea to ask them if the pitches slope when you book. I have also found many site owners, with sloping pitches, have a ready supply of extra planks available for caravanners to use, but it is good to ask when you book.
For the side to side levalling I made up a number of different length planks of 1.5" thick plywood, sealed them with varnish and angled the sides to make it easier for the wheels to ride up.
If you have a motor mover on your van the job of levelling is much easier. The planks can either be long enough to go under both wheels but I made shorter ones and put two side by side.
I have two complete sets of planks and have rarely needed to use them all. Total cost was about a tenner. (plus my valuable but free time to make them)