Do not force drinks on your guests or rush to refill their glasses when empty. Some guests may not wish to appear rude and will accept drinks they do not want. Make bottled water available. Many people will choose to drink water when they feel they have had too much to drink. Do not plan physical activities when you serve alcohol.
People are more prone to injury or mishap after drinking.
If one of your guests has been drinking and should not drive, please do not give back the car keys tp prevent driving to and avoid harm .Maybe just a little persuasion from you could mean the difference between life and death. Suggest that you or a sober friend drive your alcohol impaired friend home. The car can always be picked up at another time. Suggest that your impaired friend stay overnight in your home. Have your friend taken home in a taxi.