Some students swear by writing things out. However, I suggest that you make sure you paraphrase when you write and don't memorize verbatim. You'll recall more if you really understand something. Rote memorization, in some cases, can be the kiss of death. Reading Take an active approach to reading.
Some students read the text into a tape recorder and then listen to it.
If you can't understand something in one text, you might try finding another text. Sometimes other texts are easier to understand. For some students working with a study group aids comprehension of the material and the ability to recall what you learn. Meet on a regular basis, and take it seriously. Don't digress, reward yourselves afterwards.