[SAump]

Most folks start with their right ear over the catcher's left shoulder. Moving left behind the batter a half step gives you a better perspective of the batter's frame. Recommend it when a good catcher frames each pitch for you. Moving right behind the catcher a half step gives you a better perspective of the catcher's frame. Recommend it when a catcher is "pro-posing" a location other than where it was caught. As you work more games, you'll develop a feel for that spot.

YSMV.