> As an undergraduate student, I found that writing a summary of everything I had learned in a class was one of the best ways to study for an exam. I would just sit down with a blank piece of paper and try to summarize everything as precisely as possible. Ultimately, writing your own textbook would be a very effective way to learn the material.

Amen.

Back when I was tutoring a lot, I used to ask the students to keep a "master formula sheet" and continuously add formulas to it. In the final review session, I asked them to explain each math formula in plain English, e.g F=ma --> forces cause acceleration (and the acceleration produced by a force is inversely proportional to the mass of the object). I could immediately tell who understood the material and who was trying to get by on memorization.

Another useful exercise is to pretend you forgot your "formula sheet" and try to reproduce it from scratch. If you can't it means you're not solving enough problems---after solving 5-10 problems using a given formula, you start to remember it, and not as a string, but as an idea. You can forget a string; you can't forget an idea.