fyi, nearly everyone that succeeds in achieving morse proficiency recommend strongly against any sort of visual cues like this. It's an auditory "language" and adding visual interpretation steps just adds cognitive load and hurts in the long run. It may be fine if your goal is to learn max 5 words per minute or something extremely slow.

Like others said, such methods will not help achieve proficiency in morse. One needs to learn and associate sound patterns rather than dits and dahs