It should be cleaned to restore its natural elasticity. If it doesn't work, it is suggested to wear a thin beef tendon in the middle of the fabric, or steal a needle to sew a little on both sides of the hat.

After washing the hat, tie it with a rope. According to the length of the hat, it can be divided into 3~4 sections, and rubber bands can also be used. Naturally air-dried clothes are tied in sections in the same way, and then the rubber band or rope is disassembled after drying. You can also dry it with an iron.

Or the method is as follows:

Just tighten the hat (according to the thread knitted by wool, no wrinkles), flatten it and iron it directly. If it is not sprayed, wet the hat first; There is another way, if there is no soldering iron available, you can also use an iron cylinder (stainless steel) and just boiled water (100 degrees! ) iron directly, first wet the hat with warm water.