Andy Matuschak talks about taking notes that aren’t just for the purpose of accumulating a big library of notes but for actually thinking, developing insights, doing better work, making creative connections.

these practices aren’t about writing notes; they’re about effectively developing insight: “Better note-taking” misses the point; what matters is “better thinking”. When done well, these notes can be quite valuable: Evergreen note-writing as fundamental unit of knowledge work. –Evergreen notes

A few points:

• You need a daily routine for writing and revising evergreen notes. You need to spend significant time here. Ideally, this is the work that comes first (both in order and priority).
• an inbox for notes
• a way to separate transient notes from evergreen notes (reliable, consistent)