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Review at growing intervals

Review material at growing intervals so it stays in memory longer.

What you need

Learn the material thoroughly.
After a short interval, recall it without your notes.
If it went well, push the next review further back; if you struggled, review sooner.
Review difficult content more often and easy content less often.

The method is especially effective for long-term memory, because you remember the material for longer after each review.

Flashcard box with compartments: spread the cards over 3 to 5 boxes. Correct answers move one box on, wrong ones go back to box 1. Practise box 1 daily and the later boxes less often, for example box 1 daily, box 2 every other day, box 3 weekly.
Digitally in Anki or similar programs, with intervals set by your own study plan.

This is where we found the tip. The badge above shows how well it is backed up.

subjectguides.york.ac.uk (opens in a new tab)Spaced repetition is where you repeatedly review previously learned materials, adding increasing intervals of time between reviews“; https://www.psychologicalscience.org/observer/desirable-difficulties — „That spacing of study attempts is an effective way to create long-term learning“ (APS-Bericht über die Arbeiten von Bjork & Bjork); https://subjectguides.york.ac.uk/study-revision/leitner-system — „Correctly answered cards progress to boxes that you don't need to review as often