If they are conscious and responsive:

• Don't leave your friend! Stay with them and check often to make sure they are still conscious and responsive.
• Make certain that your friend stays on their side, not their back. 
• Keep them quiet and comfortable. If they are in the sun, move them to the shade. If cold, move them to a warm place and offer a blanket.
• Don't give them food, drink, or medication of any kind.
• Remember that only time will sober up a drunk person. Walking, showering, or drinking coffee will not help and may actually cause harm.

If the person is unconscious, semi-conscious, or unresponsive:

• Cannot be roused and are unresponsive to your voice, shaking, or pinching their skin.
• Skin is cold, clammy, pale, bluish, and/or blotchy.
• Breathing is slow - eight or fewer breaths per minute.
• Experience lapses in breathing - more than 10 seconds between breaths.
• Exhibit mental confusion, stupor, or coma.
• Have seizures, convulsions, or rigid spasms.
• Vomit while asleep or unconscious and cannot be awoken.

If any of these symptoms of alcohol overdose exist, call 911 for help, and while waiting for emergency personnel:

• Gently turn them onto their side. This will help prevent choking.
• Don't leave an unconscious person alone. Because alcohol poisoning affects the way your gag reflex works, someone with alcohol poisoning may choke on his or her own vomit and not be able to breathe. Be prepared to administer CPR.
• Remember that there is a chance that a person who has passed out may not ever regain consciousness and there is a serious risk that death could occur.