It's ok to say "no." Really.

That may be tough to hear. After all, we're constantly told to seize the moment and never let an opportunity pass us by. That's true for budding entrepreneurs, especially.

But sometimes we lose sight of what we're actually chasing. We forget to ask ourselves whether the people we meet and events we attend enrich our lives or drain the life out of us. We forget to say no.

It's a lesson too many of us learn the hard way, says Jacqueline Whitmore, etiquette coach and founder of The Protocol School of Palm Beach. When Whitmore was setting up her own business 16 years ago, she would accept every invitation that came her way -- not only because she's a self-professed "people pleaser," but because she was eager to grow her company.

It caught up to her. "I forgot to take care of my health. I missed a major doctor's appointment. And I ended up getting extremely sick," she says.

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The irony is that all of her running around wasn't actually benefiting her bottom line. "There were a lot of things that I was doing that were costing me a lot of money that had no impact on my business whatsoever," she says.

Sound familiar? Prioritize. Commit to figuring out what makes you happy, but also what helps your business grow in the right direction, Whitmore says.

Here's a full post of Whitmore's tips on when to say no. Some excerpts of particular use to entrepreneurs:

Don’t give away what you can sell. It’s easy to develop a reputation of desperation. If you say yes every time someone asks you to share your advice, you erode the value of your expertise. Your time is valuable. Any time you spend away from your business has an opportunity cost. Don’t make a habit of doling out advice or other free information; it’s your value as an entrepreneur.

Choose clients selectively. If you’ve ever had a difficult client or a customer who constantly complained about fees, you know what a headache it can be. It drains you of time, energy and resources. Particularly difficult clients can be an emotional nightmare and push you to your limit. Look for red flags when you first meet potential customers. If you sense there will be personality conflicts or the scope of the project may grow beyond the initial request, don’t be afraid to say no or recommend someone else.

Develop criteria for events. Make a list of objectives and goals for yourself and your business. When you decide to attend an event or conference, make sure you will benefit in some way by attending. In other words, measure the opportunity cost of your time commitment against the potential ROI.

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