bravetraveler
I am my experience/expertise, not my notes, so I take a very natural (read: naive/undeveloped) approach

If I/my calendar/ticket queue didn't remember it, it wasn't worth remembering.

Obviously, this isn't perfect, all kinds of trivium is forgotten. I'm not concerned; the important parts are internalized. I'm not going to forget the concept of protocols or whatever

My bag of tricks is different from others. I might need to borrow/loan: as it should be

I do want to make a point to write more momentary snapshots. A blog is the immediate thought. The things I find important change, of course, so this would be a neat record/trend

geekodour
I have terrible memory so writing things down is my only way to stay floating.

1. cheats: https://cheats.geekodour.org/ (it's a fish script that writes things into a org file which gets exported into html, i use fzf to lookup while in the cli)

2. a toolchest page: https://geekodour.org/docs/tools/primary_toolchest/ (haven't updated in many months now)

3. wiki: https://mogoz.geekodour.org/posts/

wiki(3) gets updated daily, cheats(1) get updated whenever it's a command or tactical stuff, toolchest(3) gets updated very rarely like once a month but helpful to organize the various things i work on etc.

most effective has been cheats and wiki in day to day use, i use ripgrep to search through my wiki, no fancy search.

wannabebarista
I use Obsidian to take notes with extensive cross-referencing. I mostly keep track of papers/books I read.

I used Trello for years but it eventually because too slow and clunky.

malux85
A hierarchy of folders Inside are pdfs, markdown files, images, schematics, mind maps

I frequently review them, shift things around

I have a set of spaced repetition folders which topics I am currently memorising go up and down depending on how easily and quickly I recall them when I test myself

I let the categories form naturally I don’t try and “big design up front”

The folder is regularly encrypted and synced to an always on android phone I have as a wearable computer (it has other functions too - personal llm output, on the mesh net to my personal cluster etc, connected to Bluetooth bone conduction headphones so I can hear while getting audio messages)

Works well, accessible on phone, laptop, any machines, it all resides on my NAS

kalaka
Keep writing. Write without intention. Over the years or days or months or weeks you will notice the pattern in your writing. It's a reminder that outside is disorganized, but on your brain it's pretty organised.
telesilla
Every meeting I have starts with a new Notion entry with the date and title of the meeting. Then as the meeting goes on, I'll just take notes. It's been invaluable, having years of people knowledge to fall back on when I need a contact in a certain area, or remember where I learned something, keep business records etc.
breck
I used to keep notes on programming languages in a private journal. Then I open sourced it and thanks to a lot of contributors it is now pldb.io

we also invented scrollsets along the way, a great way to organize your knowledge

p1esk
I publish papers.
speedgoose
Google Scholar and GitHub.