Yeah, there are rules. Try to minimize the things that you have to remember (a nonempty set!), and be able to derive whatever you can. Try to find mnemonic devices for remembering the things you need to remember. All that will increase understanding. But the best advice I can give is this: take subsequent courses that use linear algebra: numerical analysis, functional analysis, and quantum mechanics. I took quantum mechanics the semester after linear algebra, and I can tell you: it packs it in!