I get asked this all the time!
Prepare for batters to hit more. Strike outs usually decrease with the extra 3 feet. You now WANT batters to hit - just hit YOUR pitch. Attacking the strike zone with your best pitch and make them hit it.
Go right at batters. Keep the pitch low in the zone, on the corners and change speed often.
Technique and Practice
Work on spins, especially fastballs. Lots of top spin create downward motion on fastballs. Very effective.
Changeups need to be 40-42 mph range. Much slower than 40 mph gives the batters too much time to react at 43 feet.