Keeping the bed area cool?

What do you guys do to keep your bed cool (with camper shell, of course ) when you want to sleep?

 

I have insulation that I put between my side windows and screens. Got a roll of the aluminum bubble insulation from Home Depot, cut it to shape (with some room for airflow on the end). When I want to use it, I just pop the screen off and put the insulation in place then put the screens back. Helps keep it a little cooler during the day, and blocks out all lights at night.