Goddddd its was always a hassle for me Id usually just use most blunt method which is repeating the same kanji, filling the whole piece of paper stroke by stroke while muttering it's readings 🥹🥴 i also had a thing like. When I saw a kanji in text that I didnt recognize, id highlight it and then write it on big card and then plast it on my wall. Preferably in front of my bed so id see it every morning. Also making up sentences on your own that also include this kanji cus it like. Makes you feel it better i think. Use anki, they are cool too. Japanese language gets much easier when you always have cards on yourself. Practice writing at least for 10 minutes a day