Ask HN: How do you retain information?

I'm trying to improve my ability to learn and retain. I find writing notes after I learn to be helpful. I feel like I'm missing another step -- reviewing my notes over time to ensure I retain the information?

I've heard about techniques like spaced repetition and using software like anki for better recall. Are there other ways to help retain information?

tl;dr After studying + writing notes, what are other things you do to help you retain information?