I often start an indoor sitting with a wipe-out. It is an easy method to quickly establish the masses of light and shadow and get the drawing done before complicating matters with color.
I was introduced to this method by portrait artist Marvin Mattelson, at a workshop where he covered a huge amount of information. After doing a drawing with the wash-in method, he utilizes a prepared palette similar to the one developed in the past by Frank Reilly, except Marvin eschews the use of cadmium pigments. Frank Reilly was an instructor at The Art Students League in New York who trained many artists to paint realistic skin tones in this way. A good book to try and find on the Reilly method is entitled, “The Fine Art of Portraiture: An Academic Approach” by Frank Covino. I believe it is out of print, but can be found in libraries and sometimes for sale.
To prepare for the wipe-out, when using standard acrylic primed canvas, you need to apply a couple of coats of extra acrylic gesso well ahead of time, letting the gesso dry and sanding lightly between coats. The gesso is applied across the canvas both horizontally and vertically to smooth out the brushstrokes. If you use an oil or alkyd primed support you can skip this step.
Before beginning the drawing, the canvas is covered with an extremely thin layer of cold pressed linseed oil. The amount of oil used has to be just right, as too much will result in the paint coming off too easily and not enough will make it difficult to remove the paint right down to the bare primed canvas. Sprinkle the oil over the tip of a palette knife, rub in with a rag and then wipe off most of the oil with another clean rag or paper towel. Test to see if it is ready by rubbing a clean finger over the surface. The finger should not be shiny! Check that the oil is distributed evenly by holding the canvas at an angle to the light and looking carefully over the surface to find any dry areas. Having a thin, even coat of oil is very important to ensure that you get an even layer of paint in the next step!
On a white ceramic tile, Winsor & Newton or Michael Harding Raw Umber oil paint (a 4" strip squeezed out of the tube) is then mixed with one drop each of cold pressed linseed oil and Distilled English Turpentine, plus half a drop of clove Oil (to prevent the paint from drying too fast) and applied evenly to the support with a large brush. Try to get the paint to approximately match the skin in shadow, usually Munsell value 3 or 4, depending on the complexion of your subject.
To remove the paint, gradually rub the paint off with a rag wrapped around your finger. For more detail, you can use stomps (usually intended for drawing) or just wrap the rag around a pencil. You can also use a clean brush to remove paint from the canvas.
For darker areas, apply the paint with a brush, rubbing the oil off the canvas first for the darkest darks.
Since raw umber is a fast drying pigment, your wipe-out will most likely be dry the next day and you will be ready to start applying color.
I don’t always use this method, as I sometimes go right in with color and paint in an alla prima fashion. When I decide to start with a drawing, however, this method is a really unique and fun way to begin. It is especially good for someone just learning to paint, as it breaks down the process and makes it much easier to obtain results in an organized fashion. It is a disciplined approach that simplifies things a lot.