First, clothes stained with menstrual blood should be soaked in cold water for half an hour. Never wash with hot water, because once washed with hot water, hot water will react with cellulose in menstrual blood and it is not easy to wash off. After soaking, you can wipe it with sulfur soap or special underwear soap and wash it clean. It is suggested that the less clothes with blood, the better, because once the time is long, the blood is easy to coagulate and not easy to wash off. Secondly, if you are afraid of cold, you can put a little hot water after soaking.