A coloring method has acts of: (a) preparing a substrate having at least one display surfaces and each display surface printed with an ink layer to form a coloring area having multiple resin units mounted in the coloring area; (b) coloring the coloring area of the substrate with water-based colorants; and (c) rubbing the coloring area of the substrate. The coloring area is colored and rubbing alternately to display a special effect, like colored leather. Moreover, the coloring area can be colored by blending red, blue and yellow to obtain various colored results. The present invention is able to stimulate, inspire and develop color sensibility for children.