Let's face it, the fun has pretty much gone out of flying these days. But if your airline ticket is free, that can take some of the sting out of being crammed into a middle seat next to a crying baby. And if you're willing to put a little time and effort into a frequent-flier program, you can rack up the miles even if you rarely fly.
Make a list of airlines that serve the airport you use most often. (You wouldn't want to collect miles on an airline that doesn't fly out of your home airport.) To narrow your focus even more, make sure the airlines you list have convenient service to your most-visited cities. And it also helps if an airline lets you use its miles on another airline.
Consider the services you use when you travel: rental cars, hotels, credit cards and the like. Log on to each airline's website and get a list of its partners. Just about every airline partners with hotels, rental car companies, shopping websites and credit card companies. List all the partners next to each airline, and consider the ones you might use the most. You might like airline "A" better than airline "B," but if the first airline doesn't partner with the hotels and rental car companies you use, then the second airline would be a better choice.
Once you've chosen your airline, sign up for its frequent flyer program and make sure you are signed up with its partners. Hotel and rental car memberships are usually free, and can really help you pile up the miles when tacked on to an airline trip. They'll also send you "mileage bonus" offers in the mail, which can double or triple your miles earned in conjunction with a flight.
Apply for a credit card affiliated with the mileage program you've joined. Credit cards can really help you rack up the miles...if you pay them off in full every month. (Paying credit card interest in order to collect miles doesn't make sense financially.) Many airlines offer one mile per dollar spent, and some offer bonus miles for money spent at certain locations like grocery stores. And many times you'll get a significant bonus if you use the credit card to buy an airline ticket on your chosen airline.
While you've been getting bonus airline miles from your partner memberships, you're also piling up points in their programs as well, and some of them will let you "transfer" those points into airline miles. You'll have to decide if thousands of hotel points are worth more as a free hotel room or as frequent flier miles. A nice problem to have!