(In A Hurry so apologise for duplication)

I have two plastic mats for the car (towing makes it just as important as campervans) , moulded with grips so that you can put them under the drive wheels and get out of snow/mud - they're orange as it happens. Failing that fit-out the floor with cheap off-cuts of carpet and use them in emergency - then ditch them when muddy.

Try to remember which wheels do the driving when parking-up, if it looks dicey put the non drive wheels in the wettest part, don't be prissy about pointing in a direction - point where you can exit cleanly. remember it may be dry when you arrive but after a 4 day festival that field was not designed for camping! You will be dry, will the ground?