Think of the song 'Stayin Alive' by the Bee Gee's to guide how fast to do the compressions. One compression for every beat of the music.
Make sure there isn't anything in the mouth obstructing breathing
If the person vomits, don't panic you did nothing wrong
Tilt the head to the side and wipe out the mouth with a cloth or your fingers
Make sure you keep the airway open at all times!
Has the person responded by waking up or starting to breathe on their own?