Preparing for an at-bat does not start when you get in the batter’s box. It does not start on your way to the plate. It starts long before the first pitch of the game is even thrown.
Before the game starts, find out who is pitching. If you have faced them before, visualize their pitches. Watch them in the bullpen if possible to look for movement and release point.
Watch the opposing pitcher while you are in the dugout. Talk to your teammates and discuss each other’s at-bats. Look for patterns and signs that might indicate the pitcher is tipping his pitches.
In the on-deck circle, be aware of the situation and have a plan. Follow your routine, relax and breathe. Find the pitcher’s release point and follow the baseball.
Once you get in the batter’s box, your approach and routine should be automatic. You just need to relax and breathe. This is not the time to work on your swing. You have done that in practice and are prepared. Trust your ability and have confidence.