1. Prepare the mulberry leaves without pollution and pests, shake them and put them in a steamer with clean gauze. Boil water in the pot, put the steamer in the pot and cover it tightly.

2. Uncover the lid immediately after the fire is steamed, put it in a clean container and spread it out. Put the mulberry leaves in a hot pot and turn them over with a wooden shovel.

3. After the water evaporates by half, use a small steady fire to evaporate. Pour the mulberry leaves into a clean container, spread them out to dry, cool them, and sift off the fine powder with a sieve.