This group of marker renderings is typical of the style that used for fast, overnight assignments. I would first do a pencil sketch, using it for an underlay which I would trace on layout paper with a technical pen. Then I would color the ink drawing with markers, a fast, effective method to produce a lot of work in a short time. Time is always short for storyboard artists.
This assignment consisted of about 15 frames.
This was one of a series of ad comps that I rendered for one of my Chicago clients. I used the same method as I did on the storyboards above. You can see that this technique works very well on larger renderings like this.