Preoperative skin preparation, as one of the important preventive and curative measures to prevent postoperative incisional infections, includes measures such as shaving of the skin in the operative field, cleaning and disinfection of the skin. Here is mainly for patient friends. I. Time of preoperative skin preparation For those who have hair growth in the surgical site, special attention is paid to preoperative skin preparation. The traditional belief is that the focus of preoperative skin preparation is to shave the skin of the surgical area, which should be done 1 day before surgery. However, the Guidelines for the Prevention of Surgical Incisional Infections published by the Centers for Disease Control and Prevention state that the closer the skin preparation is to the time of surgery, the better. Therefore, it is recommended that patients should prepare their skin before coming to the hospital on the day of their surgery appointment. Skin preparation razors are generally available at pharmacies. When using a razor, you should pay attention to the angle between the razor and the skin, and be gentle to avoid shaving the skin. It is best to choose a disposable razor to prevent cross infection caused by incomplete disinfection. For scalp surgery, the skin can be prepared by medical staff after coming to our hospital; for vulva, armpit and face (especially for men with thick beard), it is better to prepare the skin by yourself. For patients who need facial surgery, clean the skin thoroughly before coming to the hospital, do not use makeup, concealer, sunscreen, isolation cream, etc. It is especially important to clean the umbilicus before abdominal surgery. The umbilicus is a place where the human body can easily hide dirt and grime, and in terms of umbilical skin preparation, if there are hard foreign bodies in the umbilical fossa, it is best to soften them with oil and then wash them with soap and water.