Generally, it is boiled in water, and the shape is restored at high temperature. 1, we can use a steam iron. As long as one hand puts the steam iron about two centimeters above the clothes, let the steam soften the fibers slowly, and then use the other hand to shape the sweater. With both hands, the sweater can gradually return to the original state of tight fibers, just like new ones. 2. Just soak the sweater in cold white vinegar water in turn, and then gently rub the sweater with conditioner. Leave the conditioner on the sweater for about 30 minutes, then wash it with cold water, wring it out and spread it on a towel to dry. When the sweater is air-dried, fold it, put it in a sealed bag and freeze it in the refrigerator for 24 hours. When you take it out the next day, it won't pilling. 3. Soak the sweater in warm water at 30℃-50℃, or steam it in a pot for 20 minutes, let it slowly recover its shape until it basically recovers, and then put it in cold water for setting. Finally, remember not to wring it out when drying, but to dry it flat. This is a very effective method when the sweater is washed too much.