You don't need to be Doug Ulman, CEO of the Livestrong Foundation, to know that using a high-profile celebrity as your spokesperson can be either a boom and a bust. The history of celebrity branding is replete with successes, such as Bill Cosby for Jello, Michael Jordan for Nike and Hanes, and William Shatner for Priceline. However, brands have been burned when top celebrities went off-track: O.J. Simpson for Hertz (domestic abuse), Michael Vick for Coke and Nike (dog fighting), Michael Phelps for Kellogg and Rosetta Stone (marijuana), and Kate Moss for Chanel and Burberry (cocaine), to name a few.
Celebrities are popular and followd by many people so it makes sense that there is a strong allure for marketers to enlist one to pitch their product. A celebrity can capture consumers' attention for your brand, link it with their own personal brand and associate their positive attributes with those of your product.
On the other hand celebrities can go terribly off script and take the brand with them. Plus there are other potential downsides, such as the additional cost of hiring a celebrity, which will impact your budget. And when watching ads, consumers may focus more on the celebrity and less on your brand. And ultimately, the approach may not work. One 2010 study  found that the majority of celebrity ads were no more effective than non-celebrity ones. So here are some important rules to follow if you're considering celebrity branding as part of your strategy.
Determine if celebrity branding fits strategically.
Before one uses any marketing tactic it's important to think first about how it supports your overall marketing strategy. It's easy to get enamored with the idea of hiring a celebrity and hobnobbing with them. But that's a big mistake. You need to think first about what your brand stands for, who is your target, what the goals are for your campaign and also consider your budget. Only with factors such as these in mind can you determine if a celebrity branding approach will help you execute your strategy more successfully than using a non-celebrity approach.
Pick the right celebrity.
Once you've decided that, yes, a celebrity spokesperson makes sense, you need to think about who that celebrity might be. You need to select one whose personality and story support the brand attributes you are trying to communicate to consumers. You also should select one that doesn't endorse too many products, otherwise your brand will just get lost in the mix.
Kim and Wayne Pick, Executive Creative Directors at RAPP  provide some do's and don'ts. "Don't make a celebrity a shill. Or a puppet. Or a mannequin. Don't put words in their mouth that they wouldn't say naturally or that don't seem authentic to them. Don't cram a celebrity into an ad."
"Do give them the license to contribute to the creative, so that it is true to them. Do make sure it's a natural fit and a benefit for both parties. Do look for the unexpected, yet relevant, connections as they're more likely to provoke interest."
Determine the creative approach.
Once you've got the right celebrity you need to think about how the ads will communicate the message you want the celebrity to deliver. This Troy Polamalu ad  for Head & Shoulders uses the football player's well-known hair to make the point that the product gives you thicker looking hair. This ad was noted in the above study as an example of a celebrity ad that paid off.
Another example here is that of Diddy and Ciroc. Chris Raih, Founder and Managing Director of Zambezi  notes that, "Ciroc vodka and Diddy are archetypal of a good union. Diddy's personal brand is really about being 'the life of the party' and Ciroc is positioned as the 'official drink of celebrations.'"
Have the right relationship.
The relationship between a brand and a celebrity should not just be a marriage of convenience. It should help the celebrity as well. Steve Stoute, founder and CEO of Translation  puts it best, "Look to manage a relationship--not a contract, and make sure the partnership is a win for the celebrity partner outside of the check. I've always found the best deals I've ever done, were ones in which the celebrity had something to gain more than just a check."
Another key point here is managing trust. Brian Cupps, the man responsible for bring NBA star Dwyane Wade on as a spokesperson for Chinese sportswear maker Li-Ning  explains, "Don't over promise. I have seen many great partnerships unravel quickly due to the fact that expectations weren't managed up front and things were said or promised only with the interest of getting a deal done. It is much easier to manage shortcomings you may have as a company or brand early on as opposed to having those things discovered after the fact. If and when things go sideways with big deals like these, they are very hard to get back on track organically because trust is lost."
Create your own celebrity
If you don't wish to pay the cost of hiring a celebrity or can't find one that makes sense for your brand then another option is to develop your own "celebrity." That's what Progressive did when they created the character "Flo"  (actress Stephanie Courtney) to be their brand spokesperson.
Although Flo appeared in more than 80 Progressive ads it took more than just showing up to turn Flo from a simple character into a spokes-star. Pete Favat, the Chief Creative Officer at Arnold Worldwide , the agency that developed Flo for Progressive, explains, "Flo’s evolution from character to spokesperson to celebrity started with solid casting. We chose the actress, Stephanie Courtney, based on her comedic and improvisation skills on top of how she 'popped' on screen. Her ability to roll with quick, snappy and most times unscripted responses to the other actors has been imperative to her likeability. She was initially cast for a 3-part TV campaign in 2008. We ran those three spots and people liked her. They really liked her. So we made more."
Today Flo has almost 5 million fans on Facebook and was named No. 1 Ad Icon nationally in a head-to-head battle by Entertainment Weekly, plus had a top-selling Halloween costume on Amazon last year.
Creating your own icon may take more time. However, it allows the opportunity to have the brand spokesperson communicate you brand message potentially more effectively and efficiently than using an existing celebrity. Unfortunately, even brand-created celebrities can create problems; the Dell Dude's arrest for trying to purchase marijuana and the Aflac duck's voice Gilbert Gottfried tweeting jokes about Japan's Tsunami in Japan attest to that.
See if it's working.
After the campaign is released it's time to see if it's working. Is there positive buzz about it on social media? Is there increasing the awareness, consideration and purchasing of our brand? Are people linking our brand with our celebrity? Are the celebrity's key attributes that we want to associate our brand with actually transferring to our product? If so, great! If not, corrective action needs to be taken.
Cut the cord when it's not working.
Obviously it's not fun conversation to tell a celebrity that their services are no longer needed. The inevitable press about the split is never helpful to either side, especially if its a messy divorce. However, if you determine your celebrity brand approach isn't working it's better to end the relationship as soon as possible and move on. Allowing the agreement to expire is a less problematic approach but if there's a scandal obviously you may need to terminate the relationship earlier.
Celebrity branding done right it can be very powerful. To make sure it is take the time to follow the steps above.
--Mark McNeilly is the author of three books (including the popular Sun Tzu and the Art of Business: Six Principles for Managers) and a Lecturer at UNC’s Kenan-Flagler Business School. Prior to that he was a marketing executive with experience at IBM and Lenovo. You can follow him at @markmcneilly or learn more at suntzustrategies.com