I worked at Disney World for over 3 years. Here are 10 of the biggest mistakes I've seen tourists make.

Instead of buying water at the parks, I like to bring a reusable bottle that I can easily refill at one of the many water fountains.

If you don't have a bottle, any quick-service food location on the property will also be able to give you a free cup of ice water.

Either way, it's a great way to save money because the single-use water bottles at Disney are at least $3.50 each.

Working at Disney World, I experienced really cold days in winter and extremely hot weather during the summer.

Check the weather close to your visit so you're not taken by surprise and can pack anything you might need. During the summer, I always carry sandals or flip-flops to change into if (when) it rains, so I don't have to deal with wet tennis shoes.

Packing a poncho is also a great idea — you'll likely get rained on at some point during your day at the parks.

There are definitely seasons that are busier than others at Disney World. But more often than not, there's always going to be a lot of people at the parks.

If you're looking to sit down for lunch or dinner, I recommend making reservations ahead of time. Some restaurants will accept walk-ins, but your wait time might be extremely long.

Another tip I've found useful is aiming to eat before or after the typical mealtimes. The restaurants won't be empty, but they'll probably be less busy than they are right at 12 p.m. or 6 p.m.

A lot of Disney merchandise can be found in multiple locations throughout the property, including at Disney Springs, the shopping, dining, and entertainment district. But there are certain products that are specific to a location, limited-edition, or simply selling quickly.

Speaking from experience, if you see something you really like, don't hesitate and buy it then and there. Odds are you won't be able to find it again as easily.

There are so many things to do at Disney World, and the reality is, you won't be able to do it all.

Instead of exhausting yourself, prioritize the activities that are important to you and your family. And make sure to take breaks so you can recharge and continue to enjoy your trip.

Remember, there are plenty of low-key things to do at Disney Springs and the resorts as well.

In the past couple of years, there's been an increase in people buying tons of Disney products just to resell them online. This is frowned upon, frustrating, and makes it incredibly difficult to buy popular products.

In an effort to stop this, there were times while I was working in merchandise that we had to put up signs saying guests can only buy two of the same product at a time.

Just buy what you need and allow other guests to enjoy the merchandise as well.

A lot of guests will skip Disney's professional PhotoPass opportunities to save money. But it's free to just have the photographers take your picture.

After you're trip you can use the My Disney Experience app to look at them and purchase any that you really like — you don't have to make any decisions during your day at the parks.

You can also always have a park employee take pictures of you for free on your own phone or camera.

Don't make obscene gestures for ride photos.

You won't even be able to see the picture on the screens at the end of the ride, let alone purchase it. Plus, you'll also cause the rest of the guests riding with you to lose their pictures.

I like to plan funny poses with my friends instead.

Waking up early during your Disney World trip is crucial to avoiding as many crowds as possible — especially if you're staying at a hotel on the property and get early access.

But most people who rope-drop the parks are headed for the same popular attractions.

Instead of heading that way in the morning or middle of the day, wait until the end of the night. You'll avoid standing in the sun during the hottest hours of the day, and there's a good chance most people will be watching nighttime shows or leaving the parks.

Visiting popular lands like Star Wars: Galaxy's Edge in Hollywood Studios or Pandora in Animal Kingdom at night is also a beautiful experience with the added lighting effects.

As someone who's had to work really long days at the parks and been yelled at by guests on many occasions, I can't emphasize this enough: Be nice.

We understand that big crowds, long wait times, and hot weather can lead to very stressful days for everyone. But those are never excuses to be rude to the people working. Please understand that most things are out of their hands.

Disney employees are just trying to do their jobs while dealing with so many people. I was happy to help anyone as best I could as long as they were respectful.