Always aim at the center of the center of the smallest thing you can see. The smaller the aim point, the more focused you'll be and the smaller your groups should be. Remember the old adage, "AIM SMALL, MISS SMALL."

It might help to get some of those little orange sticky dots to put in the middle of your target.

Then don't let the thought get into your head that you're shooting groups. A group is made up of individual arrows, so mentally focus on each individual arrow as you shoot. If the one before didn't hit where you wanted, forget it. It's history and there's nothing you can do about it. The only arrow that matters is the one on your bow right now!