> Spaced repetition is, by far, the most effective cognitive hack I’ve used.

I totally second that. Well, sleep and exercise do amazing things for you too, but if you need to memorize things, I don't know of a quicker method than spaced repetition.

Check out Leitner system: https://en.m.wikipedia.org/wiki/Leitner_system

Flashcards Deluxe supports Leitner, I don't know about Anki?

https://play.google.com/store/apps/details?id=com.orangeorap... (I have no relation to that app, I just find it incredibly useful).