Man, you're makin' me flash here. I was a volunteer "honorary scout master" when my son was in scouts, and did the same as you, 'cept I used what the kids used. Lucky for us, we were on a lake that was very low, and there was no risk of it coming up in months and months, so we had a lot of driftwood, and big rocks with some nice soft sand in between. That made it pretty easy to simply cover over the space between a couple of rocks, scoop out hip and shoulder holes in the sand, and sleep like babies. Of course a bunch of older scouts had to make a midnight (or maybe later, who knows) raid, screaming and yelling at the top of their lungs. Such fun...