Here's a little information on dry brush technique.

http://www.artistdaily.com/blogs/watercolor/watercolor-florence-strauss-building-layers-of-drybrush-color?et_mid=951131&rid=253926102&utm_source=newsletter&utm_campaign=ad-cja-nl-170619&utm_content=951131_EDT_ADE170619&utm_medium=email