Here's a piece I made last week for the LA Times using a slightly different method inspired by a graduate student at one of the schools where I teach. Her method is similar to my usual technique however she makes custom-made texture areas for each piece. She uses graphite to sketch the texture areas on vellum and then uses them to make screens for screen printing.
So, for me, rather than collaging a pre-existing texture, for this piece I pencil-filled in the large color areas using a 3B graphite pencil, scanned them in, and then converted them to the individual color areas. I like the fact that I am hand-making each color area as well which results in unique textures for each image area.
The LA Times article this piece accompanied was written by a chef discussing his profession.
Below are the pencil-filled areas (along with some of the line work) drawn on tracing paper with a 3B pencil and then set to high contrast using the Threshold command in Photoshop (Image>Adjustments>Threshold). The background was built using the face element.