1.Supine position, on the ground or hard board

2. Open the airway and clear the foreign body in the mouth

3. Determine whether there is breathing

4. If you are not breathing, immediately blow your breath twice

5. Keeping the head back, check the carotid artery with the other hand for pulsation

6. If there is a pulse, just blow twice immediately mouth-to-mouth

7. If there is no pulse, perform chest compressions immediately

8. For every 15 presses, blow 2 times from mouth to mouth, then reposition, press again 15 times, and repeat.

9. After 1 minute of CPR, or after four consecutive cycles, check for changes in respiration, pulse, and pupil.