Here the plate is being wiped in a series of circular motions.
With each wipe the paper towel is changed to a fresh clean surface, until the plate is cleaned down to the amout of ink desired.
At first you wipe a lot of ink off, then finish up with a light touch, according to how much ink you want left on the plate.
Sometimes certain areas are wiped more, a cotton swab cleans small highlighted areas that are going to be the color of the paper.
Want to see this copper plate in the several stages of being engraved before printing?