1.Prepare the skin the day before surgery, with the upper border to the level of the upper edge of the auricle at 2 cm and the posterior to the midline of the occipital area. 2.Shower and dressing the day before surgery. 3.Empty the intestine by oral laxative or enema one day before surgery. 4.Antibiotic skin test one day before surgery. 5.Fast water in the morning of the operation day, but a small amount of water can be used to deliver antihypertensive, hypoglycemic and pain medication. 6.Give preoperative medication in the morning of the operation day according to the anesthesiologist’s instruction.