Question about Geosets

[Koboid]

So, I was reading the modeling tutorials in the tutorial section and learned quite a bit of stuff, but when I got to the geoset section, it made no sense. It seemed like he assumed the readers of the tutorial would know how to create the geosets already, or he just forgot to add some things.

Either way, is there anyone willing to teach me how to make a geoset? Thanks in advance!