Post-Facebook IPO wisdom, from one CEO to another

May 18, 2012, 4:00 PM UTC

Zipcar CEO Scott Griffith

FORTUNE — Bust out the streamers and party hats, everybody, it’s Facebook IPO Day! The excitement aside, many of us are wondering what it all means.

How, for example, will Facebook actually grow enough to merit its massive valuation? Will the company be able to make money off of mobile? Will it figure out how to sell the massive amounts of user market data it has collected without starting a privacy war? And will this change what happens when I “like” my cousin’s sepia-toned picture of mozzarella sticks?

It’s easy for us, and probably Mark Zuckerberg, to get caught up in the IPO whirlwind. No one knows that better than Scott Griffith, the CEO of Zipcar (ZIP) who took his company public on April 11, 2011 for $18.00 per-share, a higher price than analysts expected. The IPO, Griffith says, “was probably the best branding event we’ve ever had.”

Brand recognition isn’t part of Facebook’s (FB) problem. The tech company went public today at a starting share price of $38 per-share, which means the company is being valued at about $104 billion and could raise more than $18.4 billion in proceeds.

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Still, in addition to the cash influx and media hype, going public calls for management tweaks. About a year after Zipcar’s IPO, Griffith has been thinking about what he learned after Zipcar’s transition from a private to public company, and he has some words of wisdom for others in the same position.

Welcome to the jungle

Right when you hit the market, you have to have a stronger sense of who you are than ever, Griffith says, and you have to learn how to express it to other people. “I do think you have to learn the art of the sound byte.” You may know who you are, but, he says, “It’s important to simplify the company’s story down to a very few key messages that you say over and over and over again.”

All of a sudden, he says, CEOs need to redirect time previously devoted to running the business towards communicating the business’ purpose and plan to shareholders and the media. At meetings, earnings calls, and press events, the CEO is now the voice of the company. “Certainly when you’re first public, they want the CEO in the room,” Griffith says. CEOs in that position have to shift the hours in their day to become available to the outside world.

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That change doesn’t just call for time management skills, it also requires language tweaks that may seem meaningless but do make a difference. “You know, CEOs are famous for making these declarative statements — ‘We are going to, we will’ — that’s what we do for a living. Now I find myself having to say ‘We believe’ a lot. Lawyers want to coach you a little bit on that, and that’s understandable.”

Mind the market, but don’t let it control your every move

Griffith says it’s also important to take the new scrutiny with a grain of salt. Yes, post-IPO CEOs need to be much more careful, but they cannot obsess over the market fluctuations and analyst responses that become part of their daily lives.

This is especially true for companies such as Zipcar and Facebook, Griffith says, which are actually creating a new market. “These are game-changing, iconic companies that are transforming a whole industry — you cannot get mired in the quarter.” Or even the year: Zipcar’s stock has dropped in value by almost 28%, year-to-date.

Amazon’s (AMZN) Jeff Bezos has been able to take the fluctuations in stride, Griffith argues. Bezos is known for making major investments to grow his company even at times when the cash loss may bruise Amazon’s quarterly earnings. Wall Street may ping pong, and that is stressful, but CEOs should stick to their guns, Griffith says.

Meet your new shareholders…

New public companies get plenty of attention from analysts and shareholders, but another crucial shift happens internally after the IPO. Namely, employees who have been busting their butts to get to this point now have stock options that have real value. CEOs have got to be on the ball about discussing those changes with as much clarity as they communicate to outside stakeholders.

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“The real benefit is there’s this incentive and alignment for team members to improve performance of the company, that’s the brilliance of the stock options,” Griffith says. But on the other hand, employees who haven’t had to think about it before now have a huge appetite to learn more about the value of the stock.

To help with that, Griffith says, Zipcar organizes a formal internal quarterly earnings call that takes on a similar tone to that of an analyst call. Griffith says it’s been successful at keeping his employees informed.

IPO advice from someone who has been there boils down to some fairly universal principles: keeping a clear head, communicating well to the outside world but not obsessing over its reactions, and speaking clearly to your home team.

“What I’ve found,”Griffith says, “is that most companies are not as good as their highest stock price would say they are, and they’re probably never as bad as their lowest stock price would say. Wall Street has trouble finding truth in the middle.” Fanfare aside, the middle is likely where even the most-hyped companies truly live.