1. The medicinal materials should be processed, shredded and broken in accordance with the law, and then blown up in accordance with the provisions of each category; medicinal materials with a light texture and not resistant to frying should be added after other medicinal materials are fried until they become brown.
2. Refining the oil after explosives to "drop water into beads", add red lead to a certain temperature, stir to fully mix, and spray with clear water. Soak the ointment in clean water.
3. Volatile drugs, mineral drugs and valuable drugs should be ground into fine powders and added before spreading. The temperature should not exceed 70°C.
Fourth, the plaster should be black and shiny, oily and delicate, moderately old, spread evenly, without erythema, no fins, and can be pasted on the skin without moving after heating.
5. The plaster should be sealed and stored in a cool place.