The project was lots of fun! Just google it and you'll get many tutorials. Basically you can either just stick on your crayons and melt them with a hair dryer, or let the crayons melt in the sun (no control here), or melt the tip of the crayon and draw short strokes or just dab on paper to create small dots. We decided to try a combination today.
That's all. Do give it a try. Just be warned, lots of mess! and lots of time needed to complete this.