Ankiのボタンは迷ったらGood/Again
Again: Select this when your answer is incorrect or when you couldn't recall the answer. If your answer is partially correct, you should be strict with yourself: if it counts as a fail in a real-life context outside of Anki, then it counts as a fail in Anki as well. You'll typically use this button about 5-20% of the time.
Hard: Select this button when your answer is correct, but you had doubts about it or it took a long time to recall.
Good: Select this when your answer is correct, but it took some mental effort to recall it. When Anki is used properly, this should be the most commonly used button. You'll typically use this button about 80-95% of the time.
Easy: Select this if your answer is correct and it took no mental effort to recall it.
FSRS can adapt to almost any habit, except for one: pressing "Hard" instead of "Again" when you forget the information. When you press "Hard", FSRS assumes you have recalled the information correctly (though with hesitation and a lot of mental effort). If you press "Hard" when you have failed to recall the information, all intervals will be unreasonably high. So, if you have this habit, please change it and use "Again" when you forget the information. 忘れたら必ず「Again」（「Hard」を使わない）
迷ったら「Good」（「Hard」を多用しない）
簡単すぎるものは「Easy」、ただし慎重に
定期的にFSRSの「Optimize」を実行し、最適化する