The basics always stand you in good stead. Always say please and thank you. Give praise to other people, but don’t overdo it. Encourage other people. Never laugh at anybody. Do not be a snob. Don’t discuss brand names or the cost of things. Be broad minded—other people are not required to like the things you like, and your liking something does not make it high class. Move outside your social group to include others.
Never draw attention to yourself. Don’t even think about yourself. Your focus should be on other people. Let them lead the conversation. Even if you’re not particularly interested in what they have to say, try to give them a chance. You may learn something new or be exposed to a new idea. But on the other hand, you’re not required to torture yourself. If you really can’t stand listening to them anymore, say “I think I see a friend I haven’t greeted yet”, and leave.
If the conversation veers into territory of disagreement, and the subject is very important to you, be direct and firm and kind—not wishy washy—and express your differing opinion, using a softening phrase such as “It seems to me that…”, or “In my experience…” And if you find yourself not seeing eye to eye, don’t make assumptions about the other person’s motivations, native intelligence, sanity, past experience, etc.
Be gracious and kind when other people make mistakes. Don’t take offence—if someone has outright insulted you, you can gently correct them with a phrase like “That wasn’t a nice thing to say.” If they continue to insist they are right, leave (see above phrase for moving on to a new person).
If other people make mistakes pretend not to see. If it’s huge, like falling down or breaking something, intervene in the least obtrusive way possible. If somebody else has already rescued the person, back off. They’re probably humiliated, and the kindest thing you can do is pretend you didn’t see.
Before you leave, say your goodbyes to your host.
Remember to thank them the next day for inviting you.