If you do not want the colours to mix, be sure to wait for the first layer to dry before applying another colour over it or up against it.
Hint: to make beautiful, thin lines, you mix the Water Make-up with Cleansing Lotion instead of water.
Draw a line down from the middle of the nose (between the nostrils) to the upper lip. This line gets wider as you get towards the upper lip and you then draw it along the upper lip to the corners of the mouth. Continue the line beyond the corners of the mouth and upwards in a curved shape.