How would you recommend making a Padded Cell

[JacketMaster]

I have long been interested in making a padded cell for myself, It would be a fantasy come true if I could make one to match my very particular specifications. Unfortunately, it'd likely be several years at least before I could make one, but a man can dream! In the interim, I'd like to ask, what materials would you recommend someone use and what the general process would be for constructing one. Again, I'm very particular in my desires, so here's some narrowing down.

For starters, I want the entire room covered. Everything. No hard floor, exposed frames, or easily seen doorhandles. I also want the padding to be thick. REALLY thick. So much so that you couldn't normally feel anything solid no matter how hard you jumped or ran into it. It'd like for it to be soft, a nice and squishy outer layer. I'd assume it would need layers, with a very squishy outer layer (either memory foam or that squishy kind they make those toys out of), a more dense middle layer, and a springy high-resistance bottom layer (maybe a mattress, but that'd probably be pretty expensive and unwieldy). The fabric/material coating it is also something I'm not sure of, either a soft fabric that's nice and breathable, or a thin vinyl that will be less comfortable but easier to clean, but I'm open to suggestions!

I might as well post an image that gives a general picture of what I want, here's the big inspiration for me-



Just putting this out there, lemme know about you think!