I think different methods work for different people. Whether you’re getting ready for an oral presentation or just taking a GAMSAT preparation course like this one, you will have to try different methods to see what works for you. Try revising, studying with a highlighter, or just try what I do. First, I’ll make written summaries of what I just reviewed. Writing about something helps it stick to my memory, and of course, I can re-read those summaries when I need a refresher.
Aside from that, you should also make sure you study in a calm environment and avoid getting distracted. Every time you get distracted, you need to stop and refocus on what you were doing, making it hard for you to understand what you’re reading and making it hard for you to commit it to memory. In addition, you get a fragmented view of the topic if you’re constantly distracted, and the mind isn’t good at holding fragmented information.