Summarize the following:
Without adding food coloring, the crystals will be clear and take on the color of your pipe cleaners. If you want the crystals to be tinted with color, add 4 drops of food coloring to the solution and stir it in. Try adding 4 drops of blue food coloring for light blue snowflakes, or 2 drops of blue and 2 drops of red food coloring for purple snowflakes.

Summary:
Add 3 drops of food coloring, if desired.