Full answer
Decades of cognitive science research converge on one finding: re-reading and highlighting feel productive but produce poor long-term retention. The two techniques with the strongest evidence behind them are active recall — retrieving information from memory without looking — and spaced repetition, which spaces review sessions across expanding time intervals.
Active recall means closing the book and trying to remember what you just read. Flashcards are the classic tool, but writing a brief summary from memory, doing practice problems without looking at examples, or explaining concepts aloud to yourself ("the Feynman technique") all activate the same mechanism. The act of struggling to retrieve something strengthens the memory trace far more than passively re-reading it.
Spaced repetition means reviewing material at increasing intervals — for example: 1 day after first learning, then 3 days, then 7 days, then 14 days. Apps like Anki automate this scheduling automatically based on how well you recalled each card. Cramming the night before compresses all review into one session and produces much faster forgetting after the exam.
For focus during study sessions, the Pomodoro method — 25 minutes of focused work followed by a 5-minute break — reduces cognitive fatigue and maintains concentration across longer sessions. Eliminate phone notifications entirely during study blocks; research consistently shows that even the presence of a phone on a desk (screen down, silent) reduces available working memory.