I used some scraps leftover from the window quilts I made for her room a couple of months ago. Sewed two pieces together to get a large enough piece. Lay it on the chair and cut around it making sure I left enough fabric that it would go underneath. Then sewed elastic around the edge, pulling it taught as I sewed. The elastic pulls the fabric underneath so it stays put.
If a person really wants to live a more frugal life then making repairs should be a part of that life. I sometimes let repairs go undone until they bug me mentally to the point I "have" to get it done. It's not that I don't want to make repairs. It's that I don't believe I have the time. I must keep reminding myself that any projects worthy of doing deserve time to get done.
If a person has more time than money.... repairs are worth the effort and should be a part of the simple life.
When I was younger, repairs were a normal part of my routine. It might be as simple as sewing on a button or patching a tear on jeans. Sometimes it was replacing a door knob or tightening a chair leg or painting a dresser. Back then, I thought nothing of taking the time to make repairs. After all I grew up in a time when we were taught.... if it's usable then repair it. If it's not usable.... make something else out of it. It was just natural to make repairs.
As my quilting career took off, more and more repairs got shoved aside in my quest to stay ahead of the long waiting list of tops to quilt. I worked more so I could pay someone to do my repairs so I could work more and pay more people to do still other repairs. At heart I'm a do-it-yourselfer. I like getting my hands dirty so to speak. There's just something very satisfying about knowing I did it myself.
Now that I'm moving back toward a simpler life, repairs are once again becoming a part of my routine. The seat cover for the chair is a temporary fix. Yes, I do know how to do upholstery work too. I've been a do-it-yourselfer for my whole life. Of course, I can't do everything; but, what I don't know, I'm sure there is a website or a book that will tell me how.