Use Crayola. These are the best and have the best color saturation. Use a paper that will grip the color evenly. I like Stonehenge or illustration board. Have a good hand_held sharpener handy. Always try to keep a point on the crayon. This makes it go on more evenly. Apply the crayon in a professional manner. Just like you would any other fine art tool, use control and be deliberate. Don't become five years old again!
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.