Need to prepare: water, basin, flour, alkaline noodles, salt, white vinegar.

1. First put the casings into a basin, pour a handful of flour into it, and grasp it evenly with your hands, as shown in the picture.

2. Wait until the flour is evenly grasped and then wash it with clean water, as shown in the picture below.

3. Then add alkali and white rice vinegar and mix well, and keep grasping it with your hands until it is evenly distributed, as shown in the picture below.

4. Wait until the white rice vinegar and alkali are added together, then rub it vigorously, and then rinse it with clean water, as shown in the picture.

5. Add white rice vinegar and salt below, rub it evenly with your hands, and then wash it with clean water, as shown in the picture below.

6. Next, just turn over all the washed casings, as shown in the picture below.

7. Finally, the casings are cleaned, as shown in the picture below.