At work I'm fairly methodical about planning ahead for the next day, week, month--almost as methodical about planning as I am about disregarding the plan when the time comes. It involves OneNote and I should explain it sometime--it's a useful system.
One key part of it is making a new note page for every (pertinent) meeting in my calendar. It serves two purposes: (1) to line up the day's or week's events; (2) to catch notes from the meeting. The first part I'm good at; the second part I'm not.
I think that a slight frame of reference shift would improve the actual keeping of notes. I tell myself: it's about the information. It's about keeping receipts. It's like an old school engineering lab notebook. (A fine ritual itself.) But I don't think that's the most useful thing. The notes themselves aren't as important as the ritual of the notes. Why don't I write meeting notes as frequently as I think I should? Can't keep notes when you're not paying attention. Can't keep notes when you're talking too much (or doing that thing where you're just waiting for an opening to talk). Being present in that moment is the real value.
I am good at keeping notes when I am or feel responsible for keeping notes for the group in a meeting. Perhaps tapping into that is another method to self-motivate.