It varies depending on how relaxed you are. Anywhere from 1/2" to 2". The more relaxed you are, the larger the blip.
If you peek above the top edge, you should be able to see something clearly a couple feet beyond.
Give your awareness to the outside white margins as you turn a page per second in a steady rhythm and comfortable pace. It's alot like the vision we use when we're driving. A soft gaze for everything in our peripheral field.
And, feel free to get creative with the closing affirmation statements. Direct your inner mind to jumpstart your activation sessions. Request to recall a dream sequence where your inner mind reveals a solution or insight.