This is from a DVD that accompanies the book Fashion Illustration for Designers by Kathryn Hagen. Ms. Hagen is a fashion illustration instructor at Otis College.
Ms. Hagen is a master at mixing media to achieve life-like and beautiful results. Her tools include: Copic markers, Prismacolor pencils and markers, Tombo brush pens, gouache, liner pens and Milky Gel pens.
Even if you don't study fashion illustraion per se, this books is an excellent resource for improving your skills with drawing and rendering materials. You can find it here
LINK to Book
LINK to Ms. Hagen videos on You Tube.