You solve a beautiful combination on Monday and miss the same idea on Saturday. That is not a lack of talent; it is how memory works. Spaced repetition is the simplest tool there is against it.
How forgetting works
In the 1880s, Hermann Ebbinghaus measured how quickly he forgot what he had learned: fast at first, then more slowly. Each time you recall something just as it is fading, it fades more slowly afterwards. So the best moment to review is neither every day nor once a month, but at growing intervals: a day, a few days, a week, a month.
A spaced repetition system keeps that schedule for you. It shows you a card, you answer, and it decides when you see the card again: sooner if you missed it, later if it was easy.
Why it suits chess
Chess strength rests on patterns: mates, tactics, endings and typical plans. Strong players recognise thousands of them at a glance. Patterns are exactly what flashcards teach well, and a chess position makes a perfect card: the position is the question, and the move is the answer.
- Tactics: the positions where you missed a fork, a pin or a mate.
- Endings: the positions every player should know, such as the Lucena and Philidor positions, or king and pawn against king.
- Openings: the moves of your repertoire, and the traps in it.
- Your own mistakes: the positions from your games where a better move was there to find.
Making good chess cards
- One idea per card. A card should ask one question with one clear answer, such as “White to move and win material”, not “What happens here?”
- Find the move before you turn the card. Say it or play it. Recognising an answer is not the same as finding it.
- Keep the few that matter. Twenty cards you review are worth more than two hundred you skip. Add a handful from each chapter or game.
- Grade yourself honestly. If you hesitated or guessed, count it as missed. The schedule is only as good as your answers.
- A little every day. Ten minutes of reviews a day keeps the pile small; skipping a week makes it grow.
From your books to your cards
The hard part of spaced repetition for chess has always been making the cards: setting up each position, entering its answer, and keeping it with its source. GreyChess does that part for you. Make a course from a chapter of a PDF chess book, and its diagrams become positions to solve, each answered by the book’s own move. They then join your flashcards, ten new ones a day, each coming back just before you would forget it.
Puzzles you miss in rated training become flashcards too, and so do the mistakes from your own Lichess and Chess.com games.
Start with one chapter. In a month, you will remember it better than any book you have only read.