I like the conduit support method!
But for fabric, my wife and mother-in-law put me onto cheap bed sheets years ago when we were doing huge Christmas displays of ceramic buildings, etc.. The villages cities were built on stacked sheets of Styrofoam, so the skirting was simply pinned into the foam, hand pleated as we went along.
Mom was a whiz on the sewing machine (always at the ready), so she bought Twin Bed sheets, cutting them in half, sewing a simple hem on the cut edge. When I say "cheap", those gals knew the true meaning of the word and the place(s) and times of the year to find them. Sadly, the Christmas displays became more work than time/age could deal with. The skirts became drop cloths and/or dust covers for other situations.
But, they did the job...….cheaply!