1. Know your audience.

Universal Pictures and Dreamworks LLC
This is especially critical in determining the course of your very first greeting—do you shake hands or go for a European-style cheek kiss? (Note: two for Italians, three for Swiss.) You want to avoid a whole LeBron James-meets-royalty situation and blindside your girlfriend’s mother with a bear hug when she’s going in for a polite handshake.
2. Dress the part.

Universal
What? I always wear a cardi over my dress shirt while reading the Times. And my legs just cross this way naturally. This is what’s also known as marriage material, friends.
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3. Come bearing gifts.

Walt Disney Pictures
Alcohol and chocolates are
perfectly acceptable options for your host. Bonus points if you can show up with something personal. Also: will there be children on hand? Children never forget the boyfriend who showed up empty-handed and ruined Christmas for all (the stakes are this high).
4. Eat the food.

New Line Cinema
Now’s not the time to take up a new no-sugar-gluten-free-green-juice cleanse. Unless there are pre-existing allergy or dietary concerns—in which case, your S.O. would have hopefully passed along that helpful info beforehand—the answer to “would you like to try my Bundt cake?” is always yes. (Sorry.)
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5. Stay out of sibling rivalries.

Lee Mendelson Film Productions
You are up against an age-old family feud of which you have neither the history nor ammunition to compete. Back away to the nearest dessert tray (stuff face with cookies when asked for input).
6. Make friends with their pet.

Universal Pictures
And just hope they’re dog people (cats will invariably see right through you).
7. Be prepared—for anything.

Paramount Pictures
You will be grilled. And it may not even be intentional, but the sizing-up of your sense of humor/career prospects/entire being will be an enjoyable family pastime this Christmas. Have a few engaging yet tasteful personal anecdotes on hand.
8. Keep banter light and impersonal.

Miramax Films
That said, as the eggnog flows and you grow more comfortable in your surroundings, continue to be mindful of the stories you share. You don’t want to get in with the family at the expense of your partner (to whom you’ll have to account for your storytelling later on the ride home).
9. Have an out.

Columbia Pictures
A code word, an escape plan, a fake death (yours?)—something that will allow you to make a graceful exit when the time is right. (This usually coincides with the emptying of the last wine bottle.)
10. Just be cool.

Twentieth Century Fox Film Corporation
There’s a reason you’re here on this most festive of stressful family holidays: someone obviously thinks you’re worth bringing around.
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