Dana Brown's demo on the Ampersand Art website.
When the gesso is dry, I add a little water to the back of the paper and gently rub with my fingers. Layers of the paper will come off leaving the black and white image on the gessoed Claybord surface. This process takes a while and you must be patient and remove the paper gently as to not remove the image itself. As you see in the photo, I work small parts of the image at a time and brush off the paper flakes with a soft brush.
I like both of these methods as a quick alternative to detailed line drawings as a base for color. I will varnish these pieces and they will hang just as they are shown here.