What is a habit?
A habit is an achievement of efficiency. It uses the invisible learning process to solidify neuron connections in the brain along required pathways and to prevent complication or interference from other pathways. In the mind as representation of behavior of the brain, this translates to a reduction in the amount of thought and focus necessary to complete a task.
Done being scientific. What does this mean in human terms? Habit and thought are antithetical.
The more you think about a thing, the less it can become habit. The deeper a habit is ingrained, the less you think about it. The way to make a habit is to engage in the act of doing a thing repetitively and to avoid thinking about it beyond what is necessary. The way to unlearn a habit therefore, is to focus on it with all the awareness you can muster. Find the reason for the habit, and stare at it mercilessly. Keep your mental eyes on it and convince your mind that this is not an activity you will engage in without consideration and focus. Eventually your mind will capitulate and will begin to disable the mechanism that keeps the process in question moving outside of your conscious control.
Consider as an example: the first time you learned to walk up stairs. You were probably very young and probably needed a few tries to do it successfully, even if your legs were long enough to take it in strides and your muscles strong enough to propel you upward. Eventually your body and mind habituated to it and you found yourself flying up and down stairs with ease. But since then, have you ever tried focusing on climbing stairs? Concentrating on what each muscle group in your legs were engaging in, where your eyes were looking, where your hands and arms were, your sense of balance, breathing, etc. all at one time? What do you think would happen? Undoubtedly you would flounder just as you did as the small child first confronted with a new method of crossing terrain. The mind simply cannot handle so much focus and concentrated effort while also being efficient, which makes complete sense from a logical point of view, but the ramifications of which are too often lost.
Habits are very powerful, and like any power can be abused. The habits we form at any time only become more difficult to observe as the years go on. Eventually we forget the reasons why we set the habits in motion, and may find ourselves needing to revisit them. But old habits die hard, as they say in common language, and knowing you have a bad habit many years old is sometimes not enough to unmake it. There are times when very old memories need to be dredged up, painful as they are, and brought to the surface so we can see clearly where the habit started. Habits like this cannot be fought directly; you cannot hope for victory by fighting a war inside your mind. You must find a way to use your hidden ability to reverse a habit by focusing at its source, and staring long and hard enough at it to convince your mind this is not something it can hide anymore. Keep it in the open sunlight and it will shrivel and die. Then, you’ll have a clean slate upon which to rewrite the way you behave as a person in life.