I've mentioned that the very first home improvement project I ever finished was putting knobs on the drawers on my kitchen cabinets. I'm not sure why the previous owner never did it. The drawers were kind of a pain to open just by pulling on the edges. It turned out to be a decent little project. The drawers consist of the drawer itself and the oak facing that screws onto it. To install the knobs, I had to unscrew the facings (easy enough), drill a hole in the exact center of each (a pain), countersink the hole on back side of each facing for the screw head (another pain), install the knob (very easy), and reinstall the facing (easy enough). It took most of an afternoon to finish, but the results were worth it.
The cabinet doors were less of a pain to open by grabbing the edges, and there were a lot of them, so I put them way down the To Do list. It's just that lately the little pads on the back have begun to stick to the face frames, making the darn things harder to open. I needed more leverage for some of them, so it was time to bite the bullet. Fortunately, this part of the job didn't really require a lot of overthinking. The doors were just that, no attached facings, so I wouldn't have to uninstall anything first. The knobs were all going to be in exactly the same position on the corner of each door, so I wouldn't have to worry about centering knobs on varying door widths. It should be easy peasy. My only worry was that I might have trouble finding the same knobs almost six years later, but a quick trip up to Home Depot proved that my preferred knobs are classics. Or something. Anyway, they had plenty of them in stock.
One thing I did need to figure out was how to make sure the holes I drilled for the screws were all equidistant from the corners' edges. I took a little piece of scrap plywood, and carefully drilled a hole of the proper diameter in it at the desired position. Then I nailed fences of thin plywood onto the edges that were to match up with the edges on the corner of the door, extending them on both sides to make the jig reversible. After that it was easy peasy. Hold the jig on the door with one hand, and drill the hole. Clean up any splinters and dust, and install the knobs. The whole job took about an hour and a half, and it looks great.