Nike’s been taking heat recently over its apparent sponsorship re-signing of convicted dog-fighting ring master and NFL quarterback Michael Vick.

The day after Vick’s agent announced the deal, Nike went into damage control mode: they did provide him with Nike-branded gear, a Nike rep says, but never offered to re-sign him to a sponsorship. Sounds reasonable, but the damage was done – and Vick remains, however tenuously, linked to the Nike brand.

Thinking about bringing in some star power to give one of your brands a boost? Learn from Nike’s mistakes. Here’s how:

1. Make a credible link between the celebrity and your product.
Your celebrity sponsor needs to embody values that are consistent with your core brand values. Ask yourself this: could I realistically imagine this person using my product? If the answer is no, you’re barking up the wrong tree. The Buick-Tiger Woods relationship, for example, has always been a stretch for me. I just don’t believe Tiger Woods drives a Buick Rendezvous on the weekends. And isn’t that the point of the relationship? To convince a younger audience that if Tiger Woods drives a Buick, so should you?

2. Align your brand with a stronger brand.
Does the celebrity you’re considering have a brand that is at least as strong (or stronger) than yours? Maybe it’s a gut check, but start with a quick survey to suss out public opinion/awareness of this person. The celebrity you choose has to be easily recognizable by your target or there’s no point.

3. Do a background check.
Do your due diligence to try and understand who this person is. Is there a controversy lurking in the shadows waiting to leap out and sabotage your campaign? Better to know sooner than later.

4. Be prepared for problems.
If the wheels come off, what’s your contingency plan? Think about what could go wrong and how you would handle it. Then make a plan.

5. Measure your success.
Set specific objectives at the outset and then monitor closely if the relationship is having the desired impact. If it’s not, adjust your tactics or cut them loose.

Just remember, like any relationship there are good times and not so good times. By making informed decisions before you get hitched, you’ll be much better positioned for a long and prosperous union.