first you should make sure that the scene is safe then make sure that the person you are attending is laying flat on their back and on a flat surface and then tap the top of their shoulders and say "ARE YOU OK ,ARE YOU OK" twice then shout to the nearest person and tell them to "CALL 911 AND TELL THEM TO BRING THE AED" then start doing 30 compressions and two breaths
but the answer to your question is in the part when you make sure the scene is safe and when you ask them are you ok but i hope i answered you question
Answer: 1. Check the scene and the person. Make sure the scene is safe, then tap the person on the shoulder and shout "Are you OK?" to ensure that the person needs help.
