Answer

I don’t really have one. Beyond the fact that you need to be interested in the material, if it connects for you to other topics and creates a web whose parts are linked together, that helps with remembering. Someone who has a method finds it easier to remember things, because he sorts them according to their place in the web (including pros and cons, points within that web).
Let me tell you some advice I once got from the lecturer I studied with in Bnei Brak. We were learning the Talmudic passage of “for Heaven has already sanctified it” in tractate Sanhedrin. I suggested an interpretation there that is not found among the medieval authorities or later authorities, even though it is the simple and obvious interpretation, and I wondered why no one says it. He referred me to a book by Rabbi Eliezer Silver of Cincinnati, Afnei Erez, which gives that interpretation. I was surprised to see that he knew that source, and he told me that many years earlier he had read it during the repetition of the Amidah in the afternoon prayer, in a book that was in the Beit Yechiel kollel (at the end of Rabbi Akiva Street). He also told me that I could find the book there (it wasn’t commonly available). I asked him how he remembered what he had read during the repetition of the Amidah years earlier, while I read all the time and don’t remember. He told me that when he reads, he does so with attention to the material being read and not just to pass the time, and he also mentally summarizes for himself what he read (and in that way also fits it into his web). That’s the advice I have.