If a drowning person suffers from loss of consciousness and cardiac arrest, he or she needs to take cardiopulmonary resuscitation (CPR) immediately, including opening the airway, artificial respiration, chest compressions, etc.; if the patient is conscious, the patient’s vital signs should be closely monitored, and attention should be paid to preventing the cold and keeping warm until the arrival of the first aiders. 1. For loss of consciousness: (1) open the airway: the rescuer kneels on one side of the drowning person, presses the forehead with one hand and holds the jaw with the other hand, opens the airway, and removes foreign objects such as mud, water plants and dentures from the drowning person’s mouth and nose. (2) Artificial respiration: Under the premise that the airway is clear, the rescuer pinches the nostrils of the drowning person with the thumb and forefinger, wraps the lips around the drowning person’s lips, and blows 3~5 times. In the artificial respiration, the rescuer can use clothing, and if possible, can use gauze, breathing film pads in the patient’s mouth, in order to protect the rescuer; for the drowning patient, opening the airway and artificial respiration is a very important first aid method. (3) Chest compression: the root of the palm of the hand is placed at the midpoint of the line connecting the two nipples, the middle and lower part of the sternum, the wrists of the two hands are overlapped, the ten fingers are crossed and interlocked, the two arms are vertical, and the weight of the body is used to press downward to a depth of not less than 5 centimeters. Be sure to press more than 100 times per minute, and perform mouth-to-mouth artificial respiration 2 times after 30 compressions. Repeat the above operation, and check whether the drowning person’s breathing and consciousness recover every 5 cycles until the emergency personnel arrive. 2. For those who are conscious: Pacify the drowning person and place him/her in a more comfortable position; stay beside the drowning person and closely observe his/her vital signs until the emergency personnel arrive. At the same time, remove wet clothing for the drowning person and cover him/her with clean clothing to keep him/her warm.