Always Color in a Consistent Direction. This is my first tip. It will make a bigger impact on the end result than anything else and any age can use it! The changes in direction, shown on the red kidney below, on the left side, are what make it look sloppy, even though I carefully stayed in the lines. Coloring in a consistent direction, as seen on the other kidney, is easier on the eyes and ends up looking very tidy!
How to Crayon Tint. To crayon tint, your embroidery, start by transferring your design to the fabric. I recommend using a finely sharpened regular pencil, as it won't require water or be affected by ironing. Place the fabric in an embroidery hoop so the back of the fabric can press against a flat surface and color the design as desired.