Being invited feels great, but forgetting to let your host know whether you’ll show up is extremely rude, especially when the host may be going all out with the meal and possibly even gifts.

“The host has enough of their plate without having to guess how many people to cater for,” says Jo Hayes, founder of EtiquetteExpert.org. “A well-mannered guest RSVP promptly, graciously, in the manner which the invitation directs (e.g. if it says email, don’t call in your RSVP), and asks if there is anything they can bring.”

While some parties are open to all, if you RSVP for two and bring a third wheel (including kids or pets) without prior notice, that’s a major no-no. Not only does it put the host in an awkward position, it can also cause disruption as there might not be enough food, seats or even gifts for the extra guests.

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While this might not be necessary at a large company party, bringing a small token of appreciation is always considered good manners at dinner parties and other small gatherings.

“Even if the host insists guests not bring a thing, it’s good manners to bring at least a small gift for the host,” says Hayes. This could be anything from a bouquet of flowers (poinsettias are lovely for the holidays), a box of chocolates or a drink to share.

“Ensure there’s plenty of food and drink for everyone, or your event might be remembered for all the wrong reasons,” says Elizabeth Soos, founder of the Auersmont School of Etiquette and Protocol, based in Australia.

As a host, that means preparing enough food and drink, respecting dietary restrictions and offering non-alcoholic beverages. As a guest, that means sharing generously rather than hogging one dish or dessert!

If you’re inviting someone over for a Christmas dinner or a New Year’s Eve party, your guests are going to expect at least a little holiday atmosphere. “Festive touches like seasonal decorations, music, and thoughtful lighting can transform a gathering, energizing your guests and making them feel good,” says Soos. “A well-curated vibe isn’t just decorative — it sets the tone for the entire party.”

As a guest, be respectful of the ambiance the host has set by not hijacking the playlist, rearranging the decor or getting rowdy from having too much to drink.

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Hosting a party often means bringing together lots of different people who don’t know one another or may not naturally mesh right off the bat. If you’re a host, it’s up to you to introduce guests to one another and help ease them into socializing (or at least to enlist your most extroverted friend to do this for you).

But if your host is busy, experts agree it’s up to you as a guest to mingle, engage others and make it a great and memorable holiday party for all. Don’t be afraid to step outside your comfort zone!

It’s easy to accidentally go overboard with alcohol at a holiday party, but it’s important to keep things respectable, especially if you’re celebrating with co-workers. “Excessive drinking can lead to unprofessional behavior — think loud conversations, inappropriate jokes or even regrettable actions,” reminds Soos.

Stay in control by eating enough and drinking plenty of water so as not to wake up with a headache and regrets.

Etiquette experts say you should steer clear of controversial topics (yes, even in the wake of an election) to keep things light. “If a potentially controversial topic comes up, keep comments very neutral, and graciously steer the conversation back onto safer ground,” says Hayes.

As a guest, you can always excuse yourself from the conversation; as a host, you can intervene and do whatever is needed to ensure the well-being of your guests and get the festivities back on track.

Listen, you don’t have to spend the entire party hovering behind your host. But offering to help once or twice shows that you not only understand how difficult hosting can be, but that you also appreciate their efforts.

“Whether it’s setting the table, chopping vegetables, or washing the dishes, lending a hand shows thoughtfulness and gratitude for their efforts,” says Soos.

Know the saying, “You don’t have to go home, but you can’t stay here?” That goes for holiday parties as well. Hayes says once most guests have left, the music is off and the hosts are gathering up trash, you can safely assume the party is over. After offering to help clean up, politely thank your host for a lovely and festive evening, gather your things and head home.