TIPS:

Bat Angle
Correcting a Weak Swing
Finishing the Swing
Flat-Snap Hitting
Front Toe Closed
Hitting Off Front Leg
Level Swing
Looping
Lunging and Over Striding
On-Deck Preparation
One Swing
Perfecting the Stride
Plate Coverage
Poor Timing
Proper Hitting Goals
Seeing the Ball
Stance vs Swing
Staying Closed
Stepping Out on Pitch
The Two-Strike Swing

Most of these tips come from the book Illustrated Hitting Guide with permission from the author.

Staying Closed Before the Swing

Prematurely opening of the hips and shoulders robs hitters of power. This problem is most common among younger players who begin to drift open while waiting for the ball to approach the plate. In some cases this can be corrected by striding later (if the stride is in fact too early). This can also occur when the batter’s head isn’t picking up the ball.

Opening up helps the head to turn to get a better view. Thus, getting the head in proper position in the stance and maintaining it through the stride might correct this problem. For many other hitters, drifting open is a result of wanting to pull the ball regardless of where it is pitched.

Hitters need to realize that they will get more power on the inside pitch they can pull if they stay closed until they swing and that pitches on the outside part of the plate shouldn’t be pulled anyway. Telling a hitter to point his front shoulder at the ball when tracking it to the plate appears to work for some players in correcting this problem.