I had one recently. We ordered extra fabric to make “sleeves” for the arms of the chairs. It didn’t come in and didn’t come in. We phoned and gosh, darn it was there the next day…….go figure. We brought it home and it sat here for the week-end.
Then as I was working away on a new wall hanging, perhaps baby quilt, someone who shall remain nameless asked about “those sleeves.”
I finished what I was doing and went to the left-overs box and grabbed a remnant and after measuring made a prototype. Holy!!!!! It was almost perfect. A bit of adjustment on it and I was set to go.I cut all the fabric and I cut carefully as this stuff was not inexpensive. I brought it upstairs and started to sew the first set. I couldn’t remember how I had done the first one. Ah, well, it did fit and that was most important.
These were for Karl’s chair. I thought I better do his first. Then I set to making mine. Well, lo and behold, the light bulb came on and I did these
the way I had done the sample. The fit like a glove and the ends are just fantastic, even if I do say so myself. 
When I was done I sat at the computer and wrote up the directions. I even mentioned the thread manufacturer and the number. I’m keeping the sample too. I don’t have a lot of fabric left. One yard doesn’t go very far.
They are done and on the chairs. They look pretty darn good for someone who didn’t really know what she was doing.