Unless a celebrity dies, the social media world will be focused on one topic and one topic only today: the election. That means the people managing social media for brands have a unique opportunity to boost engagement, or hurt their reputations badly, by sharing the right and wrong things on Twitter, Facebook, and so on.

Although we live in a free country, and you can say just about anything short of shouting fire in a crowded theater (or its equivalent), there are certain topics to avoid so the harsh spotlight of social media isn’t cast upon you.

At the same time, there are ways to write about this historic day without getting into trouble.

Here’s a social media guide for brands on Election Day 2012.

Avoid the social media rumor mill.

Before the emergence of social media, press outlets leaned heavily on “exit polls” to report from polling places on Election Day. They offered a real-time snapshot of how the electorate was leaning as the day progressed, or so said the prevailing wisdom. In elections past, exit polls swung wildly, offering an inaccurate portrait of the race.

This time around Twitter will be the dipstick for reporters filing stories before the election totals start pouring in. And, as we all know, Twitter is rampant with rumors.

Be very careful about what you retweet on Election Day. Apply a journalist’s skepticism to the tweets you see—remember the old adage from the City News Bureau of Chicago: “If your mother tells you she loves you, check it out with two independent sources”—before you start sharing them from a corporate account or personal account. If something seems fishy, it’s probably false.

Don’t go anywhere near bitter partisanship.

Most brands avoid taking a direct political stance. The money that the companies or their executives donate to candidates and causes might do the talking for them, but brands rarely stake a position.

This year, however, a number of bosses have made their positions on clear, from a business-owner telling his employees to vote for Mitt Romney to a department store expressing its support for same-sex marriage.

In general, don’t make any political claims on social media unless your boss looks you in the eye and tells you to tweet something like, “I think we’re inviting God’s judgment on our nation,” at the risk of being fired. And even then, think twice about sending it.

If your company is leaning left or right publicly, avoid dropping partisan bombs in your Twitter feed or Facebook page. It will only inflame other partisans and make your social media properties look like a town hall meeting circa summer 2010.

Don’t ask people who they’re voting for.

On Election Day, asking your followers or fans on Facebook or Twitter to weigh in on the candidate for whom they’re voting might seem like a no brainer for sparking conversation. And it is brainless.

Stay away from that question. Otherwise, you’re providing a forum for your fans to get nasty with one another. People will express their opinions—many of which will be vitriolic and perhaps offensive—on your page, making you look bad in return.

Exercise caution in your promotions.

It never fails: A crisis, disaster, or altogether momentous event happens and a marketer is there—usually on Twitter—to try to capitalize from it.

Don’t be that marketer. Learn from those at Kenneth Cole, Microsoft Zune, Gap, and others—stay away from promotions that take advantage of an important news event.

For instance, Macy’s and Hotels.com are holding an Election Day sale online, in which shoppers enter a coupon code to receive a discount. That’s pretty innocuous.

Here’s how Macy’s (or a company like it) could get itself into trouble with this sale: A news story emerges that people are waiting in line for up to six hours to vote, setting Twitter abuzz about the tragedy and inequity of the situation; in response, Macy’s sends a tweet saying, “Stuck in an epic line to vote? Take advantage of our Election Day while you wait. Democracy never looked so stylish.”

Right now it might seem harmless, but with tempers flaring, any company that promoted itself in such a way would become an easy target of Election Day vitriol.

Be mindful of personal vs. professional accounts.

When you punch out for the day, you might head to the polls and tweet from your personal account: “Just voted for [CANDIDATE], suck it [OTHER CANDIDATE].”

Seconds later, you realize you haven’t logged out of your client’s account on TweetDeck and you just—oh, yes you did—put that update on the client’s Twitter feed. And now it’s time to freshen up that résumé.

Make sure you’re not tweeting from your company's or client’s account in general, although especially on Election Day.

Careful about scheduling tweets or Facebook updates.

If the news networks start calling it for one of the candidates and you decide to call it a night early and pre-schedule your brand’s tweets—don’t. By many indications, this election is going to be tight. Best to play it safe. You don’t want your Facebook account to pull a “Dewey Defeats Truman.”

What to tweet and share on Facebook.

Despite the many pitfalls, you should still consider updating your social media properties with something about Election Day. It will be the talk of social media, media outlets, and water coolers; you’ll want to tap the Zeitgeist to grab eyeballs and stir engagement. In that case, try plugging in one of these three tweets or Facebook posts:

• The this-or-that update: Ask your followers or fans what gets your vote among things that aren't candidates, such as your products. For instance, if your client makes granola bars, you could ask: “What gets your vote: the extra chewy granola bar or the honey and oats?” Tossing in a picture of the products side by side makes it even better.

• The “reward yourself” update: Simply pose the question, “Reward yourself if you voted by ______.” And then make a suggestion for people who voted on ways to reward themselves.

• Blank for president update: Try making a suggestion on something brand related to run for president in the next election. “______ for president in 2016.”

If nothing else, the easiest and safest update for a brand is to simply encourage people to vote on Election Day. A gentle reminder to exercise a civic right can go a long way.

Kevin Allen contributed to this story.