My go-to for memorizing numbers is Goroawase (0 = ma, 1 = i/hi, 2 = ni/fu/tsu etc.). It is less flexible in comparison (you can't choose the vowels freely) but

My go-to for memorizing numbers is Goroawase (0 = ma, 1 = i/hi, 2 = ni/fu/tsu etc.). It is less flexible in comparison (you can't choose the vowels freely) but uses less phonemes, so I think it's more intuitive for an English speaker to learn (e. g. you don't have to know the difference between ka and kha).