Booking travel is so easy to do, yet all too often we wind up spending more than we wanted.

Thank fee-happy airlines for that -- there's no limit to what they'll charge for, from meals to checked bags and flimsy pillows. According to the U.S. Bureau of Transportation Statistics, airlines made $3.3 billion in baggage fees alone in 2011.

With summer travel season in full swing, we've rounded up the best money-saving tips out there.

1. Test The 24-Hour Rule

After you book, check the next morning to see if the price of your airfare fell.

If it did, give the airline a call to cancel your flight and often you can rebook without penalty.

2. Take Last-Minute Trips

Airlines are known to cut prices when they can't fill planes for an upcoming weekend trip.

On Tuesday, they'll email offers for the coming weekend or following one to fliers who signed up for alerts. Travelers can leave Friday night or anytime Saturday, then return on Monday or Tuesday.

3. Chase The Fare, Not The Destination

Kayak (Nasdaq: KYAK) has an explore tool is useful for searching multiple airline fares at a time. You'll instantly see a map with all the destinations listed under a set budget.

4. Leave On A Wednesday

It's the cheapest day to do it, according to FareCompare.com, especially for domestic travel.

Per the website: 'The day with the most seats is likely to have better supply, and thus ... more empty seats that require discounting to fill the plane -- meaning they'll have to release more seats at their cheapest price point.'

5. Book On Tuesday At 3 p.m. Eastern

A study by Farecompare.com found this was the best time to buy airline tickets and shop for domestic travel.

6. Check Twitter And Facebook

Airlines have been experimenting with blasting fares via Twitter, Facebook (Nasdaq: FB) and other social media outlets, especially JetBlue (Nasdaq: JBLU), reports the AP. But you have to be fast: Some deals can be gone within hours.

'If you find something, jump on it,' said John DiScala, who travels frequently and writes about it at JohnnyJet.com.

Some airlines announce special sales to Facebook fans as well.

7. Fly Two Different Airlines

Sometimes it's worth it to mix and match. Most airlines now sell one-way flights at reasonable prices, meaning one might be cheaper for the outbound flight while the other works better for the return.

You could even fly to one airport and depart from another.

8. Become A Frequent Flier

It pays to cozy up to your airline of choice.

Become an elite member of the airline's frequent-flier program or use a credit card that's tied to the airline to get a leg up on other travelers, said U.S. News' Daniel Bortz.

Likewise, if you're using a credit card that offers rewards, check to see if those rewards can be redeemed for miles or travel gift cards, suggested Ask Mr. Credit Card.

9. Fly Out Early

The first flight of the morning is usually the cheapest, Bortz said.

The next-cheapest flight times are during or after lunch or around dinner time.

10. Sign Up For Free Alerts From AirfareWatchdog.com

With this site, you'll get pinged when prices fall and receive some excellent deals. The site uses real people to vet the deals rather than computers, so you're bound to turn up some offerings you wouldn't have found otherwise.

According to founder George Hobia: 'We only send updates when we think we've found a good deal, whereas other sites might update you when a flight drops $2.'

11. Use FlightFox To Search For Special Fares

Much in the way AirfareWatchdog relies on a travel agent to sniff out the best deals, FlightFox uses multipleexperts (called 'flight hackers') to do the hard work for you.

It costs only $29, and the fee is fully refundable, according to the site's front page.

You can even rattle off a list of specific demands that a computer can't check, or travel novices wouldn't include to refine your search, said Money Talks News' Brandon Ballenger.

12. Search For Deals In The Morning

Early morning is the time you'll see the most deals, Bortz said, although some airlines release discounted tickets throughout the day.

13. Take A Red-Eye

These are the absolute cheapest times to fly as they're on limited routes, Bortz said.

14. Rack Up Free Airline Miles On Rewards Sites

e-Rewards gives players tickets they can cash in for miles, while other sites like e-Miles let people cash in free miles for airfare, hotel perks and Amazon.com (Nasdaq: AMZN) gift cards, said Business Insider reporter Mandi Woodruff.

15. Search Multiple Sites

Relying on only one site to give you the low-down for low-cost airfare is silly.

Check the biggest online ticket-sellers -- Expedia (Nasdaq: EXPE), Travelocity and Orbitz (NYSE: OWW) -- and don't forget to search the little guys like Kayak, AirfareWatchdog, Yapta and Hipmunk for deals, too.

16. Book Six Weeks In Advance

A revealing study from Airlines Reporting Corporation found that the best time to purchase your airfare is about six weeks prior to travel.

The reason: Around this time, prices drop below the average fare.

17. Know Your Airport Hubs

Every airline has some kind of a deal going for certain cities, according to Ask Mr. Credit Card.

'These specials might not always be for the city you are flying to, but you might be able to get a partial discount if you take a layover in that city as part of your round trip.'

18. Be Flexible

Try adding a couple days to your trip before or after peak travel days to lower the fare, suggests the AP.

19. Don't Overlook Small Carriers

Travel search engines push smaller carriers to the bottom, but you'd be foolish to overlook them.

'Discounters don't have to be your first stop, but they should be an option,' according to Ask Mr. Credit Card.

20. Park And Fly

Some airlines have a monopoly on airports, allowing them to charge more, says the AP.

To counter this, check fares at airports 50, 75 or 100 miles from your destination. The car rental and extra travel time may be worth it.

21. Book Connecting Flights

Booking connecting flights could save you as much as $100 round-trip, according to the AP.

Just make sure you leave enough time to make your connecting flight in case the first flight arrives late.

22. Search The Actual Airline's Site

This is an oft-overlooked tip, but one well worth repeating.

Airlines can host private sales, reserving the cream of the crop for their very own websites, Bortz said.

Even without discounts, these fares can be bargain-bin-low.

23. Switch Up Your Connections

Connecting through a city that just happens to have fares on sale can also save cash.

AirfareWatchdog's 'fares to a city search' can show cheaper indirect routes to your destination. Rather than fly from New York directly to Maui, you can fly from New York to Los Angeles, then go from there to Hawaii.

Jill Krasny is a reporter for Your Money at Business Insider.

This article originally appeared at BusinessInsider.com:
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