2. Preparation: After the herring is boned, the knives are replaced with 6 pieces, and 2 herrings have 12 pieces.

3. Practice: First, marinate the herring pieces with 1 salt for one night, and press them with heavy objects during the period. The next day, take out the salt water and rinse it, then add clean water and soak it in the refrigerator for one day.