Some anchor to the tip of their nose, others put the string to the side of it. When I first started I put the string to the side. It is easier to see the peep sometimes. If you anchor to the tip of your nose sometimes it feels like you are a bit cross eyed looking through the peep. If you anchor to the side it puts the peep directly in front of your eye. Going to the side also puts the peep closer to your eye.

I think some people that shoot with glasses do it that way.

Honestly it doesn't matter how you do it, as long as you do it the same way every time.

I have seen people shoot right handed using their left eye. Looks goofy as all get out, but they were pretty good.

Paul