Planning a vacation can be exciting — but it's easy to overspend. In fact, over a third of Americans planning a summer vacation planned to use debt to pay for their trip, according to an April Bankrate survey.

"You have to really think ahead when you're planning a big, big dream trip and ask yourself, 'How much is it going to cost?'" Yanely Espinal, director of educational outreach at Next Gen Personal Finance, told CNBC at a Your Money event on Oct. 24.

There are myriad resources you can turn to for money-saving advice, from personal blogs to professional travel agents. But some common tips may not apply to you, or even be true in the first place.

Here are three common travel planning myths you can ignore, from Espinal and Cameron Sperance, senior hotels reporter at The Points Guy.

Myth No. 1: You should budget for every little thing

You can plan pretty precisely when it comes to budgeting for your flights and accommodations. But you may not have more than a general idea of how much you'll spend on shopping, food and activities once you're at your destination. 

That's OK, Espinal said. As you set aside funds for your next trip, "add a little bit more for unexpected expenses that you might not have foreseen or couldn't really plan for ahead of the trip."

This may include transportation, like cabs and Ubers, or souvenirs. And if you're traveling internationally, keep in mind that factors like currency conversions can make it extra tricky to keep track of your spending.

"Plan generally, but understand that things are gonna vary a little bit," Espinal said.

Myth No. 2: You can save money by booking your flights on a certain day

Plenty of seasoned travelers think there's a secret to getting the best deals on flights, from booking two to eight months in advance to buying airfare on a certain day of the week. However, there's generally no magic date that will grant you the lowest price.

"I have asked every airline and every booking platform about this, and I have not gotten a uniform answer for any of it," Sperance said at the event.

If you know where and when you want to go, you can track flight prices using Google Flights or your preferred travel booking site, but Sperance said your best bet is to book with flexibility.

"Book something where there aren't going to be cancellation fees, and then keep monitoring it," he said. "If you find a cheaper deal, cancel your existing reservation and rebook. That's going to give you the most peace of mind."

Myth No. 3: It pays off to hoard credit card points

For many credit card users, racking up points or miles to use on future travel is a major perk. However, it may take a while to accrue enough points to fully cover your flight or hotel, putting you at risk of seeing your points' value decline, Sperance said. 

Airlines, hotels and credit card companies change their rewards structures regularly, sometimes without much notice. And if that happens while you're saving up your points, you could lose the value of your rewards.

"Do not hoard points and miles, use them as soon as possible…use them for just a small part of the vacation, versus thinking that you're going to use them for the entirety," Sperance said. "There's a high chance that those points aren't going to be worth what they were even a couple of months ago."

Similarly, don't rack up credit card debt you can't manage in pursuit of points and miles. Interest charges will quickly wipe out any savings if you don't pay off your balance each month. You could also hurt your credit score if your charges run your credit utilization rate up too high. 

"If you have high utilization right now and you're not able to bring it down to less than 10%, then it's probably not the right time to start adding additional charges," Espinal said.

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