In the color selection of Yin Zhangshi, ivory and other colors are more popular, while green and purple seals are best not used, because these two colors represent sadness and ominous signs in the eyes of the Japanese. On the engraving pattern of the seal, it is forbidden to have lotus flowers on the seal, because the Japanese think lotus flowers are ominous demon flowers, which is contrary to China's statement. If dragons are engraved on the seal, the number of dragons should be four or nine, because in Japanese, the pronunciation of "4" is the same as "death" and the pronunciation of "9" is the same as "suffering".
The seal can be one of a square, a rectangle, a circle and an ellipse. However, because most places that need to be stamped in Japan are not very large, it is suggested that the size of the inscribed square should be in the range of 10-20mm, which is too small to be recognized, and too large will often exceed the stamped area.