1, iron with a steam iron, and iron the cloth with a steam iron. Or soak in 80 degrees hot water, as long as the fabric is elastic and suitable, it will be flat after washing and ironing.

2. Sweater fiber is characterized by softness, elasticity, extensibility and drape, and it is easy to change shape. Whether it is a new sweater or an old sweater, it can be flattened by heating and shaping.

3. The new sweater can be hung next to it when taking a shower. The steam emitted by hot water will be very flat, but it can be hung in the closet after smoking, which will also make the sweater very flat.

I really have no choice but to find a professional dry cleaner. There are professional tools in the shop to flatten sweaters.