* Forgetting to check dates. Friedmann suggests generating checklist of upcoming holidays and events -- religious, public, state or national -- at the beginning of each calendar year to ensure that you don't plan an event that conflicts with any of them. And, she warns, don't forget about major sporting events, especially if your draw is primarily male.
* Booking a site before making a visit. Beyond seeing the layout for yourself -- which can help alleviate any concerns -- Friedmann says visiting the site well in advance provides the opportunity to meet the people who will be handling your event.
* Failing to market your event. If you don't let people know about your event with plenty of advance notice, you won't get people to attend. It's all about marketing and communication.
* Signing contracts that lack specifics. The more vague your contract is, the more open it is to interpretation, Friedmann warns. Avoid phrases like "to be negotiated" or "to be determined at a later date."
* Failing to plan. The more thorough you are in your planning, the less opportunities exist for failure.
* Neglecting to check references. Why wait until the event to find out that the food is terrible and service is sloppy? By then, the event is spoiled. Talk with people who have used the facility and get their experiences before you create your own.
* Leaving important details to the last minute. The more time you have to check and recheck your details, the better chance you have of not forgetting something. If you're rushed, Friedmann says, you're more likely to forget the essentials.
* Letting someone else do the planning. Even if you hire a professional planner to do the heavy lifting, you're still responsible for directing their work. Friedmann says the role of steward is just as important, and suggests keeping a visible presence to ensure everything runs smoothly.
* Neglecting contingencies. Problems happen no matter how much planning you do. Make sure to develop contingency plans so that you have a back-up strategy should you need it. You can't plan too much.
* Trying to save money. Fight the temptation to make decisions based solely on price. "Cheap prices and good quality usually don't correlate," Friedmann says. "The next time you're tempted to make a buying decision based entirely on price, think again."