The best thing any pool player can do to improve their consistency is to establish a very quick pre-shot routine to be performed before each and every shot. Every successful professional has one they can perform in 5 seconds or less. As long as it is done the same way every time, it will serve its purposes, and there are several.
First, it assures that you get into your stance the same way every time, even when forced to take a difficult stance. With your basic stance, there are four or five steps that are always repeated (i.e. lining up the shot, placing your feet, etc.).
Second, a consistent routine lends itself to positive thinking, giving you confidence that you are doing things correctly. But more importantly, it fills your mind with positive thoughts about what you are trying to accomplish. When your mind is filled with positive thoughts, there is less room for negativity to creep into the picture.
Last, but not least, the consistency of repetition dulls the pressure in any game, especially when in competition. If you want more consistency in your game, a good pre-shot routine is a great place to start. If you need help, call me to set up a lesson.
Give it a try and good luck!