Assume you are going to hit every pitch. If you don’t, it is virtually impossible to hit a fastball even at the youth level. I like to teach the YES-YES-NO theory. Think YES when the pitcher starts his motion. Think YES when he is at his release point. Prepare to swing hard unless a NO visual cue pops up. Those cues are a pitch being up, down, in or out.
If you think “maybe” in the batter’s box, you are not being aggressive and won’t be successful.
The key is to hit the ball hard. To do that, you need to put the barrel of the bat on the ball. You have to swing at strikes to drive the baseball.
In a six inning game, the defense must record 18 outs. Make them earn every single one. Run the bases hard. Don’t swing at a pitch outside of your zone with less than two strikes. With two strikes, choke up and put the ball in play. Make the defense worry and hurry.