I rolled my tempurpedic mattress to make it small enough to bring home. I used the same knots I secure my canoe with to keep it contained and then snugged them up tight enough that I could carry it by the rope without the rope sliding out of position.
These knots let me get the canoe off the roof and in the water in a couple of minutes. The mattress not so much. The material itself wants to expand to what it thinks it the right size and it also wanted to unroll. It had a measure of success in that it found every little bit of slack and grew into and around it making it hard to even reach the knots, but also make the looser release points very snug.
Sounds like an adventure!