The usual way to gap shoot is to focus on the target, with the arrow tip out of focus in your peripheral vision. You focus on the spot you want to hit, not the spot where you place your arrow tip, unless you happen to be shooting at your point on distance. I would recommend you start off this way, as it has worked for many people.
Note that all the other ways you suggest have worked for other people at different times. The critical thing is to be consistent. If you have trained yourself to aim the usual way, and you forget and focus on your arrow tip, you will miss, miss high in my case.
If you were trained to shoot the rifle in the military, you were probably trained to focus on the front sight blade, with the target blurry. They even had a term for those who focused on the target instead: chasing the bull, which meant a circle of shots around the bulls eye with none or not many in the bulls eye. Don’t ask me why it works that way with rifles, and a different way with bows. Just one of life’s little mysteries, I guess.