Answer by
LeheckaG (1826)
Amazon MarketPlace & other on-line retailers
sell inexpensive green screens (including stands) for about $25 & up.
You require (blue or) green fabric of UNIFORM color & shading.
The flatter/tauter your screen, the better your chroma-key results;
which you can accomplish with clamps/grommets & either:
(suspended)rope, or (plumbing)tubing & (plumbing)elbows/fittings.
