When I say ‘accuracy’, what I mean is clean single note playing.
Moving laterally between adjacent holes without under/overshooting.
Skipping holes without missing your target.
Moving diagonally from a draw note in one hole to a blow note in another (and reverse)
Navigational aids: tongue, ears, bridges, muscle memory.
Rhythm… reproduce tunes you already know so that self-correction is automatic.
Of course remembering that once accuracy is comfortably achieved, tone should be automatically built in!