I wrote 'Tom Sawyer' and 'Huck Finn' for adults exclusively, and it always distressed me when I find that boys and girls have been allowed access to them. The mind that becomes soiled in youth can never again be washed clean.
Habit is habit and not to be flung out of the window by any man, but coaxed downstairs a step at a time. You cannot eliminate habits that no longer serve you. You can only replace them with new habits that support your goals. Moment by moment, you need to live with awareness and structure the habits that you include or exclude in your days.