Glazing is an excellent technique for creating skin tones that have a depth and inner glow to them because of the multiple layers of thin paint. You can either mix your skin colors beforehand and glaze with these, or use your color-theory knowledge to have the layers of color mix optically on the canvas as each layer changes the appearance of what's beneath it.
Glazes are particularly good for working up subtle differences in skin tone or color, because each glaze or layer of paint is so thin and thus changes can be very subtle. Because each new glaze is applied over dry paint, if you don't like the result you can simply wipe it off.
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