A couple ways. I start with the plane on a known flat wood surface. Loosen the knob just enough to allow the blade to make contact with the surface and retighten the knob. If the blade needs correction as to the depth left or right, a gentle tap with a brass hammer on the iron until it is correct.
Sometimes I will loosen the knob enough to wiggle the blade to position while sighting down the bottom of the plane, watching the projection which is evident by the reflection of the lighting along the blade edge.
Mike did a good job there of answering your question. A couple of guys built the same plane at our shop last weekend, and were taking shavings and the next days - both of them with little or no experience tapping an iron into place.
At the same time, you could have asked " How do you adjust this plane?"
and the answer would have been quite similar. In our opinion, the Norris adjuster is not all that fine. It gets you "in the zone" and you can pull the iron back but, it is not really going to give you 1/4 thou adjustment. So... you pay extra money for a device that gives you "coarse" adjustment (give me a minute to put on my flak jacket here...).
The adjustment process takes abotu twenty minutes to get used to and once learned about thirty seconds or less to do. If you use your plane frequently, you will probably get the plane in tune in very few taps.
Perhaps Paul Barnard will chime in here, as I am a vendor and he is a local and at arms length.