Arboreal Sling DIY Setups?

How does everyone set up their arboreal slings? I'm getting my first two - a P. Irminia and a C. Versicolor. They should be 1/2". Wanting cheap/diy ideas lol. Usually I just use bins from the dollar store and drill holes, but how do you open the top without ruining webs if they web on the lid?