 One woodcut is for outline and several others are for each colour printed, and they are carefully engraved by hand so the woodcuts can be preserved through generations.The finished picture is covered with a layer of rice paste ("hồ nếp") to strengthen the durability of its illustration and colours and afterwards dried under the sun.In the past, to prepare for Tết, craftsmen had to begin the process of making these paintings six or seven months ahead.