Dip the q-tip in dish-washing detergent. Place food coloring in the middle of the bowl with milk. Touch the color with the q-tip. The detergent will start to bond with the fats in the milk which will get all the molecules moving, carrying with them also the colors.
One of the experiments that will be shown at THE FIRST SCHOOL SCIENCE FESTIVAL AT ELEMENTARY SCHOOL "DESPOT STEFAN LAZAREVIĆ", Belgrade, Serbia.