SAN FRANCISCO (CBS 5) — Labor Day may be the unofficial end of summer, but it’s also the very beginning of the cheapest time of the year to fly, according to Nicholas Kralev, author of “Decoding Air Travel,” a new book that aims to demystify how the airlines do business.

There’s a reason for all those confusing fare schedules, rules and extra fees, according to Kralev. “The airlines have made the system complicated and frustrating for a very simple reason. They would like to make more money,” Kralev said.

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In general, the cheapest days to buy tickets are Tuesday, Wednesday and Thursday, the days airlines publish their most discounted fares. The cheapest days to fly are usually Tuesday, Wednesday and Saturday.

According to Kralev, most travel web sites are the same. But, it’s much better to buy directly from the airline because it’s easier to deal directly with an airline, rather than a third party, if you need to make a change.

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Selecting your seat when making a reservation can make the trip more comfortable. If you don’t like what’s available, try picking the least-worst seat, then going back to the airline’s website every few days and checking the seat map for your flight. It’s almost certain something better will open up.

Nicholas Kralev teaches seminars where he explains the nitty-gritty of airlines’ raw data and how to use the codes to your advantage. He will be teaching a seminar in San Francisco October 25, 2011

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