You should try not to say what you would not do. You should only say, if you feel you must, what you do not want to do. Will not can be a positive or negative it depends on what you think you will not do. More times than not it is your mind telling you things you cannot be sure of. It is more a challenge than anything else and you are pitting you against yourself. It becomes a tussle with your mind if you find yourself face to face with what you say you will not do. You must put forth an effort to hold yourself back. It requires a measure of Self-control, which could give way. If it does, one time it is too many. The only thing for sure you will not do, is a thing that you cannot do. No one knows the future.