I tried the Elmer's jar. It seemed to work OK, but it eventually thickens up after a few months. And I only patch 2-5 tubes a year. So now I wait until I have 3 or 4 punctured tubes, and use one of the small patch kits with a fresh tube of glue.

Yeah, the patches are pretty big. I usually trim off about a quarter of the patch, just on one side.

I put a patched tube on the wheel a day before I plan to ride. If it holds pressure overnight, it's usually good forever. I get one dud patch for every 6 to 8 attempts.