When you say practicing, what do you mean? Are you shooting shots, running racks or whatever, by yourself?
Perfect practice is designed to achieve a specific result. If you want to practice your speed control, you should do speed drills, and focus on that aspect of your game. If you are working on your stroke, you should do stroke drills.
Go into your practice with a specific goal. Know what you want to accomplish, and work toward that goal. If you don't have a specific goal for your practice session, it's impossible to be focused on anything.
Steve