1.Confirm loss of consciousness and respiratory pulse arrest, and call the emergency number immediately. 2.First perform chest compressions 30 times. 3, then open the airway by pressing the head and lifting the chin. 4, then mouth-to-mouth artificial respiration 2 times. 5.Repeat the above process according to 30:2 until help arrives or the injured person can move. 6.If you are unwilling or unable to do artificial respiration, you can do chest compressions only.