I have gotten so many helpful tips from process posts done by other illustrators, that I thought I'd return the favor to the kidlit community with one of my own. Hopefully it is helpful to you!
I just sent out my fall mailer a few weeks ago. At first, I planned to draw something set in a farmers market with pumpkins, gourds and the like. But then I started to think about my 4 year old son and his little "girlfriend," a neighbor in our building. They are so cute together and I thought they might make fun inspiration for my mailer. I decided to keep a seasonal theme for fall - but something warm and cozy. That is when Cafe Cocoa was born!
I always start with fast thumbnail sketches on the cheapest paper possible (I'm not kidding... I'm talking plain white copy paper from the corner Rite Aid. 6 bucks per ream!) This keeps the sketches from getting too precious and makes the bad ideas easier to throw away. These small drawings help me settle on orientation and general composition.
Once I get a sense of the direction I like, I start to sketch larger and with more detail. I'm still rocking the cheap paper at this point, because there are still many changes! These larger sketches will serve as the base for the ink work I'll do once I get a composition I'm happy with.
I'm really digging the latest sketch, so now it's time to move on to color studies. Lately I've been using Adobe's new digital drawing tool, Ink, and app, Line, to do quick studies. These tools are remarkably helpful in making it easy (and noncommittal!) to try different palettes. I drop a scan of my art into Line and overlay color on top within seconds -- the marker tool is my favorite! I do this over and over again until I feel good enough to start the final piece.
After I'm happy with the color and have a solid plan for how the final art will look, I ink all the lines by hand on a light box. I use a Pentel Pocket Brush Pen (love it!) on watercolor paper because I like the uneven quality the paper adds to the line. I'll also draw by hand any details like lines, shadows, hash marks, shapes etc using different ink pens or pencils of varying textures. I scan all the art in, and then I assemble and color (here's a great demo!) the parts in Photoshop to create the final piece.
I'm really happy with how the piece turned out. I printed them using Modern Postcard -- they have very reasonable rates and helpful customer service. The print quality was fine, though I do wish the paper stock was heavier. Ho hum - next time!