I was thinking to try something like:
- cable collars or ropes around each arm and leg, in several places. Not tighten.
- I've got S shaped metal kitchen hooks (not sharp things, usual houseware to hang things)
- a bathroom radiator.
I can hook each cable collar to that radiator that holds my weight. In several position. For safe hang a cutter with a rope.
Sorry if I'm not very good in detailing in English.