How do you do the illustrations?

I start with a pencil sketch... often I have to do quite a few before I'm happy with it. I can then trace the sketch on a lightbox onto my watercolour paper (Saunders Waterford 300gr HP), again with pencil. I would then draw the outlines in black ink with a dip-pen. Then I'd colour in everything with Ecoline inks using brushes. After that I use Faber Polychromos and Prismacolour crayons on top of that layer of ink. In the end I might have to redraw some of the black lines and use some white gouache for highlights or snowflakes.