CaptainUnderpants (love your name btw). We will be in the same boat as you this w/e. Although dh and I are seasoned BC campers this is the first time proper (ie not eurocamp) that we have camped with the dds.
We have had a practice pitch as herbie recommends!
I think being breesy is probably the key. So even if you are still trying to locate which way up the inners go 3 hours after arriving you have to appear like this is absloutely how you usually go about things.
I would avoid shouting things like
"you are so stupid I'm furious that I allowed myself to breed with you"
"STOP STOP STOP NO NO NO NO"
"call this a holiday? this is utter utter shite, I hate you all"
and Dh's classic from last years aborted trip
"I am so angry I am going to shatter into a thousand pieces"
I imagine cracking into the wine very shortly after arrival (ie put wine into car 2nd last - just before tent on the top), would avoid some of the above occuring.
Good luck this w/e