When training in table tennis, be aware of your faults point by point. When I am training with my Newgy Robo-Pong table tennis robot, I am thinking of a match situation. After I make five errors, I turn off the robot. I will not allow myself to make mistake after mistake without stopping, reflecting, making the correction, and then continuing.
Ask a better table tennis player to analyze your game point by point. When practicing with a higher-rated player, ask him or her to stop every point for two minutes and tell you what you did right and/or what you did wrong.
Take significant time between points. The official rule says that “play must be continuous.” You are allowed to step back and reflect for five seconds to realize what went right and what went wrong during the point. You are not allowed to take 60 seconds lecturing yourself while pacing the barriers. At the six point break, towel off and keep your focus on the game.
Stay in the court. Not only keep your mind on the game, but keep your eyes in the court. Even in practice, don’t let your eyes go beyond the barriers. If you see spectators or other matches or trophies or food, your mind will drift off.
Practice like it’s a tournament. After winning the World Championships, Werner Schlager was asked if he had felt much pressure during the finals. He said that he didn’t feel any pressure because for many years, he had been able to think clearly and practice as if he was in the finals. When the final came, he was just thinking like he had been training.