This run didn't turn out terribly well. I was using Sculpey clay that's been laying in my drawer for several years colored with food coloring. The food coloring didn't take too well, nor show up in pictures well. The clay itself gets very non-pliable and prone to cracking if left alone for a while after working it into decent shape. It's not a good material for the job, but very cheap (and in my case on hand already). I also have very modest skills in handling any kind of clay. Still, I'm writing it up because I feel the theory is sound and I know myself well enough to know that I won't be getting around to getting better materials or more time. I do so hoping perhaps someone else with more materials, time, patience and skill would care to elaborate/rewrite/expand on this.
Update: Evil Mad Scientist has an alternative write up now with more pro-looking pictures and illustrations using food items, if contemplating making this checking it out would be a good idea.