Option 1: Be sure to wash it by hand, not rub it hard. If you want machine washing, don't spin dry and dehydrate, just 400 rpm. Hang the wet shirt in the shade to dry. After hanging it, flatten the sheets by hand, so that it will be flat when it is dry.

Option 2: Don't wash the sheets with scalding water, and don't twist the sheets by hand during washing. You can soak them in a small amount of fabric softener during the last rinse. Also let it control the moisture, don't twist it by hand, try to flatten the folds of the sheets when drying, and lay them flat to dry. You can put a cardboard box below!

Option 3: put the clothes in a soft and economical place and wash them by machine, but don't dry them by machine. If the sheets are wrinkled like bark without unscrewing, you can unscrew them slightly by hand and shake them a few times when drying.