We just cut ours a larger width than the space and had to push it into the opening, that way it sort of holds itself up.
The order of things to do, is framing, plumbing, HVAC, electrical work, rough in inspection, insulation, insulating inspection, drywall, drywall screw inspection, finishes, including plumbing, electrical, and HVAC and final inspection.
If you just want a costume that looks like the movie, you could get some sheet aluminum, shape it the correct shape and paint itA friend of mine did that for a Halloween costume of Boba FettIf you want a real, functioning suit, Got to MIT and study engineeringThen somehow make billions of dollarsAfter that, you're on your own.
