My sister-in-law and husband bought a Finca (basic country house) in Spain and inherited a lot of furniture. There were two outdoor wicker type sofas which, though fairly sturdy, needed repainting, minor repairs and new seat cushions covers.
That’s where I came in and stupidly volunteered to make the covers. We went and chose suitable outdoor fabric for the seat cushions and found a large foam seat/mattress on my brother-in-law’s boat to fashion a back for the larger of the two sofas. After searching through a stack of furniture destined for the tip we managed to find two foam seat cushion that I cobbled together with spray contact adhesive to form a back for the smaller sofa.
Then came the very messy job of attaching wadding (I think