1.

Take an appropriate amount of dried kelp and shake off the salt, sand and other impurities on the kelp.

2.

Use enough water to completely soak the kelp so that every corner of the kelp is soaked. Pour an appropriate amount of white vinegar into the water, because white vinegar can make the kelp wet. The slime on top emerges.

3.

After ten minutes, the kelp has softened slightly, but it is still very hard. Use your hands to rub it with a little force like washing a towel, and rub each piece of kelp into pieces. The folds are stretched out, rubbed and washed.

4.

After washing it several times with clean water, soak it in enough water until it is completely stretched and soft.

5.

This will wash the kelp clean.