The mind itself is a potent instrument for change, the only one there is. All change must take place in the mind first, for all action is a result of thought and the resultant impulse or motivation. The thought system to which you subscribe gives rise to, shapes, and establishes the parameters of all action.
If you want to change your experience, and thus your life, you must become fully aware of your beliefs, conscious and unconscious, and the role they play in determining perception and action.