I've tried it but can never keep up with it. The trouble is it requires particular notebooks to be on hand when you need them, or later "clean up" efforts to in

I've tried it but can never keep up with it. The trouble is it requires particular notebooks to be on hand when you need them, or later "clean up" efforts to incorporate slapdash notes into your system. However—I do it with digital notes! Thanks to the magic of full-text search, this amounts to just making sure to add enough relevant terms when creating a note that you'll be sure to find it later when you search for it. I find anything more involved too high-friction—I will end up neglecting it until it's useless. Even folders or categories or whatever are too much and will end up a mess. Search is the only thing that works for me. I expect that if I worked off paper all the time, as most folks used to, it'd be easier to keep up with a paper indexing/TOC system. As it is, I almost never forget my phone, but have constantly forgotten various notebooks I've tried to keep. So, digital it is.