<human>:  How do I perform CPR correctly?
<bot>: First, make sure the area is safe and the person is lying on their back on a hard surface.Place the heel of one hand on the breastbone at the center of the person's chest. Place your other hand on top of, and slightly off-center of your first hand.Keeping your elbows straight, press down in the center of the chest, compressing it about 2 inches. Do this at a rate of 100 compressions per minute. If the chest does not rise with each compression, recheck the airway and give two breaths. Continue with cycles of 30 compressions and 2 breaths until help arrives or the person revives.