Reader David B. pointed me to Scott McCartney’s column in the Wall Street Journal on what to do — and what not to do — to try to save money on airfare.

Here are 8 important ways to save money:

1. There’s no magic bullet day of week to book, but there are general rules for how far in advance to book. In general you should buy domestic flights 1 to 3 months out and international trips a little farther in advance, of course only if your plans are truly firm. The cheapest fares for holiday travel get booked early. Weekends aren’t really cheaper days to buy tickets and neither are Wednesdays at 1am.

2. Know what tickets usually cost for your route. If prices are below that — buy. If prices are higher than usual you probably want to wait, especially if you’re still more than a month away from travel.

3. Start considering purchasing when your plans are firm. Don’t purchase earlier because $200 (or higher) change fees will ea you alive. Don’t start later because of rising prices for close-in departures. Don’t stress about the deal you could have gotten. . Pounce when the deal is good enough.

4. Comparison shop at Kayak.com or Hipmunk.com, sites that do the work of checking other airfare sites for you. If you really want to watch for sales, follow TheFlightDeal.com

5. Learn airfare routing rules and how to search for discount inventory, and then piece together actual flights that have the lowest inventory buckets available.

6. Throwaway ticketing can save you money. Buy a ticket that connects in the city you want to travel to, and toss the segment to the cheaper destination. Only do this with one-way tickets or only the last segment of a roundtrip, because skipping a flight will cause the rest of your trip to cancel. You may want to be super cautious and not enter your frequent flyer number into the reservation (or use a frequent flyer number of a partner airline) since it does violate airline rules to do this. And don’t check bags, or your bags will go to the city you’re ticketed to. It’s been recommended by Nate Silver in the New York Times, and the Times’ magazine The Ethicist column dubs it perfectly fine.

7. Learn how to drop fuel surcharges from international tickets.

8. If you’re buying tickets for travel outside the U.S., consider buying your tickets in the country you’re traveling from. You don’t even necessarily have to leave your desk to do it. There are fewer fares that require a local point of sale to get the cheapest prices than there used to be, be many Southeast Asian carriers only sell their cheap fares locally – and on their own website – but not through other online booking agencies.

What does Scott suggest?

Shop for one ticket at a time and you may save a lot of money.

True, a given flight may have only one seat left at the lowest fare. If you search for 2 or more seats you’ll only be presented with higher fares. You may also be able to simultaneously buy one ticket at that lower price with different browsers from more than one booking site.

He suggests also:

• Buying a positioning flight and a ticket that takes advantage of a fare war
  
• Checking codeshare partners.

Goodness knows that when American and US Airways started codesharing they were consistently underpricing each other for the same flights.

Scott says to avoid hidden city ticketing and fuel dumps.

On hidden city tickets he warns,

This plan may sound tempting, but it’s dangerous. Airline computers look for hidden-city offenses and can charge fliers the highest fare it has to the city where they ended up. Some have canceled a traveler’s elite frequent-flier status or confiscated all miles in an account.

Hidden-city ticketing also hurts other fliers because it often prompts airline computers to overbook or raise prices.

Airlines don’t generally charge walkup fares to people who use hidden city ticketing. That’s just wrong. Airlines do send debit memos to travel agencies who are regularly using the practice for their customers, but not individual travelers. Someone who frequently uses the technique and credits miles to their airline frequent flyer account could conceivably have their account shut down, which is why I advise not crediting miles to the airline you’re flying if you do this.

I think it’s a mistake to broadly declare that the technique hurts other fliers. He says airlines ‘overbook and raise prices’ to compensate. But they overbook now, they’re quite good at it, and the practice actually does keep down airfares. They rarely involuntarily deny boarding to passengers, something very expensive to the airline if they do. It’s just one factor that goes into the overbooking calculation which, when the airline bets wrong, causes them to over voluntary denied boarding compensation.

For ‘fuel dumps’ he says,

ut airlines say the trick violates fare rules and they impose penalties, so it isn’t worth trying.

You can’t really call extra attention to your tickets, by trying to change flights or upgrade with a carrier like American that re-issues tickets in such a case. You could find yourself facing an ‘add collect’ if you draw scrutiny, where you’re asked to pay the surcharge. No doubt adding strange unrelated segments to the end of your ticket looks weird, though there’s nothing improper about it.

What does concern me, depending on the airline, is adding an unrelated first segment to a trip which – if the onward carriers knew you skipped it, could cause them to cancel the rest of the itinerary.

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