The main thing is to work out an anchor that puts the nock end of the arrow directly under your master eye. That's a given, I guess. Then, as for what I do... Even though I am concentrating on the spot I want to hit, I still see the arrow in my peripheral vision and I use it. I line up the tip with the target. With the tail of the arrow directly under my eye and the tip pointing directly at the target, it has to fly down the middle.
Everything depends on getting a consistent anchor and consistent draw length. Doing everything exactly the same on each shot. When you develop consistency in your form, you'll develop accuracy on the target.
WBowhunt's suggestion is an excellent one, starting close and moving back only when and asyou meet your goals. Before we could run, we all had to start out crawling.
Some guys are like robots and have an insane capability of naturally doing exactly the same on each shot. The rest of us, we mere mortals

, have to work at it. And it doesn't come overnight. Just be patient and enjoy the ride.