First, check responsiveness and breathing. If unresponsive, call for help and emergency services. Then, place the heel of one hand on the center of the chest, with the other hand on top. Give chest compressions at least 2 inches deep, at a rate of 100–120 compressions per minute. After every 30 compressions, give 2 rescue breaths. Tilt the head back, lift the chin, and blow into the mouth until the chest rises. Continue CPR until medical help arrives or the person starts breathing again.