Whatever you would make habitual, practise it; and if you would not make a thing habitual, do not practise it, but habituate yourself to something else.

A habit is not something you have, it is something you keep doing, and it lives or dies on repetition alone. That cuts both ways: every time you do the thing you want to stop, you are not failing at quitting, you are practising. Simply not doing it is rarely enough, because the gap wants filling. The reliable move is to give the same time and trigger to something else.

Take the habit you want gone and work out exactly when and where it happens. Put a different, specific action in that slot this week, and judge yourself on whether the substitute got done rather than on whether you resisted.