One important thing about learning by repetition (which really is your only option, probably) is that it's vastly more helpful if you reinforce the information before you've forgotten it, rather than go back over your notes once it's all gone from your head. And it's much better to try to remember, rather than just go over your notes to read about it again. Remember, you're trying to train your mind to retain the information, not to forget it and look it up in your notes, so try design a system that reinforces the result you want (remembering things) rather than the result you don't want (looking things up).
(I often end up doing this wrong for a while on some new subject, and then realize that all I'm doing by re-reading the information is training my mind to not retain it.)
For a working spaced repetition system, you need two basic components:
1) a method of prompting yourself to remember the information, without reading it. You can use the chapter questions from your textbook if they're good enough, or just write down a list of questions for yourself after each lecture or after reading each book chapter. That way instead of re-reading your notes, you can test yourself against the questions later in order to prompt yourself to recall the information.
2) a schedule. Figure out, by trial and error, about how long you can retain the information. You don't want to do the next repetition when you've forgotten it all already, but you also don't want to go over twenty lists of questions every day when you have the answers memorized already.
Note that this will definitely vary with time - you could try something like doing the first repetition the day after you learned something, then a week, then a month... Adjust as needed, this is highly dependent on both person and subject. And it's not a disaster if it turns out you did forget most of the information once or twice, as long as it doesn't become a regular thing.
In addition, it's good to have different ways of reinforcing each piece of information, rather than just going over the same list of questions and answers by rote at each repetition. So maybe sometimes use the textbook questions, sometimes the questions you came up with, sometimes find a quizz online or browse the SO algorithms tag...
And try to answer the question different ways at different times - sometimes describe the algorithm/structure verbally, sometimes draw it out with diagrams and graphs, sometimes write pseudocode or even go ahead and implement something. Once in a while, not often, just reading up on it would be good too - going over your notes or textbook, SO answers, wikipedia, etc.
The more different activities/ideas your brain has associated with something, the easier it'll be to remember.
