This is an interesting technique that I made up. It is called HRC or Habit Reality Checks. How it works is that everyone has a habit. Almost everyone knows their habit, and will do it subconsiously. I for example, twirl my hair (I'm not proud of it ). I'm going to tell you how to use habits in a good way.

Step 1:

When your habit starts, go along with it for a few seconds (I can almost guarantee you will any way, because it is controled subconsiously).

Step 2:

When you notice you are doing you habit, Do a reality check. For example: If you are biting you nails, before you stop think "Can I feel myself biting something?" then look at your nail that you were biting and think "Can I see the piece of the nail that I bit off?"

Thats the technique! It should work better if you use the most frequently occuring habit that you have. Also, any time you are cutting your nails ask yourself if you can feel the pressure from the clipper on your nail, if you heard a snap as the nail was clipped, and is The piece of the nail gone now.

I hope this helps some people who are having trouble. Remember you may have to do this for up to a month before it starts working. It depends on the person.

Good luck !