Get a steady stance.
A lot of people will argue about this one, but few people actually believe that maximum accuracy, in any sport, can be achieved while standing tip-toe on one foot. Especially after drinking a few beers!
Try keeping both feet on the floor when you throw.. your game will improve in consistency, and your back won’t won’t hurt as much the next morning. Competitors in EVERY other sport have discovered the importance of a solid stance, including shooting, billiards, baseball, and golf.