Don't drink too much. There's a reason most people don't socialize with co-workers too often: letting down your hair can lead to awkward situations. Alcohol is no exception. Feel free to imbibe on the eggnog, but don't overdo it. Otherwise you could find your drunk face tagged on Facebook in the morning.
Don't canoodle the co-workers. Office policy aside, getting romantically involved with someone you work with makes work complicated. It can make for bumbling interaction after it's over, and can make it extremely difficult to work on team projects together if there are bitter feelings. Office parties are notorious for being the backdrop for one night stands, but if the temptation arises, your best bet is taking a taxi home.
Don't try to get a promotion. You have open access to talk to your boss at the holiday party, but this is no time to start pestering him for a job. He's trying to enjoy his evening, and you come off pushy and annoying if you're trying to pitch yourself for a raise. Instead, use the opportunity to have some casual conversation with him. Building the relationship will get you further than accosting him.
Stay tame. If it's in your nature to lead the conga line at any given party, and you've been known to sport a lamp shade or two at any celebration, pull back this time. You have a different relationship with the people you work with than those you typically party with, and you should maintain some decorum at the office party. Otherwise, you'll probably never live down your antics after the event.
Don't skip the party. Maybe you already know what the party will be like, given the past several have been crazy. But you should still attend. Being there shows solidarity, even if you think everyone you work with is a fool.
Avoid the leopard print leotard. If the word "party" makes you pull out your skintight, revealing clothes from the back of the closet, leave them there this time around. It's a party, but it's also work, so don't wear anything that might send the wrong signal to co-workers who haven't read this post.
Don't embark on heavy conversations. You like to unwind by talking politics and healthcare, but keep the mood light. Many people simply want to have a good time, and you might come off as Debbie Downer if you start on your soapbox. Keep the conversation easy. Joke about the funny cat video you all watched, or the Jell-O mold the receptionist brought.
Don't put your foot in your mouth. This is harder to do if you've been drinking, but if you feel like saying something, like "oh, how far along are you?" to a co-worker's wife (who may or may not be pregnant), just bite your tongue. If you're unsure of how someone will react when you say what's on your mind, it's better not to say it at all.
Don't gossip. This goes for any day in the office, but it's more tempting to huddle up and start criticizing the folks you work with at a party. Remember: you can't always trust the people you gossip with to zip their lips, so your harsh words could make it back to the subject, and then you've got a permanently awkward work situation on your hands.
If you pay attention to what you're doing and avoid embarrassments, the rest of the year won't be so awkward in the office.
Lindsay Olson is a founding partner and public relations recruiter with Paradigm Staffing and Hoojobs.com, a niche job board for public relations, communications, and social media jobs. She blogs at LindsayOlson.com, where she discusses recruiting and job search issues.