Put a patch on it, always! If I find a piece of clothing I like, I tend to keep it forever. I still have pairs of pants I bought from Hot Topic in like 2005. I've got several articles of clothing that are more patch than original, and most have some kind of patch on em somewhere. I try to keep one or two "neutral" looking outfits around for scamouflage, but a lot of times they end up patched or falling apart as well. Dental floss has always been the go to for me, much easier to find and steal than heavy duty waxed thread, but that's nice too if you can get a hold of it. Fuck safety pins for repair work. Also fuck normal thread. If you're working with fabric that frays easily, using fabric glue (or really most other kinds of glue) along the edges helps. Overlapping fabric and using larger patches will help repairs last longer.