I wouldn't say I aim at anything because I don't look at my gun sight either. Your gun will shoulder natuarlally. once you start hitting birds,
LOOK at the beek of the bird and you will find that you will start SMASH"N them off. Lots of hunters hit the birds in the breast. it's not a matter of where you are aiming but most will be looking at the breast because that is the largest part of the bird.You will hit the bird where you are looking at it.
I used to hit birds in the chest all the time until 3 years ago I got this speach from a hunter that wacks the beaks off on a regular basis.
Try it. Just LOOK at the beak!

good luck