I Quit a Bad Habit
I used to bite my nails a lot when I was little (sometimes even my toenails haha). My mom would try to get me to stop by coating them with nail polish, but I would just peel it all off.
I stopped biting once I got braces around the time I was in middle school. The braces kept me from biting the way I wanted to, and I had the braces for about 3 years, so I just kicked the habit from there.