To prevent someone from getting seriously hurt or ill at your party:

• Watch for emerging fights and drunken guests, especially as people consume more.
• Offer soda, fruit juices, water, and coffee so that guests have alternatives to alcohol.
• Discourage rapid drinking and drinking games.
• Provide plenty of appetizers, snacks, and other food. NOTE: Food only changes the pace that alcohol enters your system—it has no effect on the pace that alcohol leaves your system. Coffee, cold showers, aspirin, etc. – will not sober you up; only time will do that.
• Use cups that make no distinction between alcoholic and non-alcoholic beverages, so that people who aren’t drinking alcohol don’t feel self-conscious.
• Request identification from anyone who appears 30 years of age or younger. Guests who cannot present a valid form of ID should not be given any alcohol.
• Model appropriate behavior for your guests and be sure to communicate that becoming intoxicated is not the goal of the party.
• Make sure anyone who's visibly intoxicated doesn't receive more alcohol and not left alone. Even if the guest isn't driving, an impaired guest can hurt injured or harm others.
• Have a plan to deal with any guest who drinks too much. Before the party, ask someone reliable to help you keep things under control.
• When necessary, provide alternate transportation for impaired guests. Either call a cab or the help of sober friends to take the impaired guest home. Call 911 if there are any concerns about someone’s safety when they are intoxicated.