I find that taking notes in class helps to initially position my thoughts on the subject. I then work up my own set of notes drawing notes, text-book & other literature into a full set of notes. Sometimes I can end up with 2 lever-arch files of notes per course.
Before exams, I re-work the notes into a set of summary notes & then take mental images of each page.
This procedure sets the concepts firmly into my head & understanding. This method allowed me to carry information in my head for some 15 years after initial graduation. I then constantly reinforce, or modify this knowledge each year by reading additional books.
It becomes a life of learning, rather than merely swotting to pass a subject.
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