I use GE silicone glue for the patch, with the surfaces to be glued cleaned with Isopropyl alcohol, the glue spread and scraped thin (try popsicle sticks) on both the patch and the surface, a roller applied to the patch after application, and for good measure, sometimes clamp the patched area between two small strips of wax paper covered wood during drying. Even without the clamps, have used just the roller to bond corner and other reinforcement patches to tent flies leaving some edges unstitched with no problem. Less stitch holes on the body of the fly = less potential leakage.
Some of those flies and repairs have been in use for several years with no delamination or peeling yet. NB: That's the GE "glue", not the caulk I'm referring to. Keep the thinners on the shelf. The roller and/or clamps will help to get the excess glue out of the repair, and the alcohol on towels will clean up around the patch so long as the glue has not started to set.
It's a bit messy, but the silicone doesn't stick to your fingers for days like some of the urethanes. Still, old clothes are a must unless you want to go clothing shopping constantly (like I do - at least there is a Bean's outlet nearby).