CPR techniques are essential lifesaving methods used when someone is unresponsive and not breathing. The process involves checking for responsiveness, calling for emergency help, and starting chest compressions. Place the heel of one hand on the center of the chest, interlock fingers, and push down hard and fast at a rate of 100 to 120 compressions per minute. After 30 compressions, give two rescue breaths if trained to do so. To perform rescue breaths, tilt the person's head back slightly, pinch the nose, and seal your lips around their mouth. Deliver breaths lasting about one second each, ensuring the chest rises visibly.