Apply for a season subscription.
The season subscription brochure comes out in June. You can order a series of seven, eight, or nine operas (nine is a bit of a rarity these days). Of course, those renewing their subscriptions usually get first choice, but if you want a subscription, there's usually no reason why you can't have one somewhere in the theater. Subscriptions are also the way to go if you like your operas in the afternoon--the Saturday Matinee series are the first ones to sell out.

Subscribing also gives two advantages--the ability to exchange your tickets at the box office (see below) and a free subscription to the newly redesigned Opera News.

Order Trios, Quartets, or Mini-Series.
These are exactly like subscriptions, but shorter--and you can't exchange the tickets.

Order individual tickets by mail.
This becomes an option in the middle of the summer, when the Met releases the full season calendar. However, you can't order tickets for the second half of the season until November--unless they're for non-subscription performances.

Order tickets by phone.
A convenience or a can of worms, depending on what time of day you call. Sometimes, the service is efficient--sometimes you have to wait thirty minutes on hold before they tell you the tickets are not yet available. And yes, you have to pay a $5.50 handling charge per ticket. Your call: (212) 362-6000.

Order at the Future Sales Box Office.
Starting in the last week of August, the Met makes all remaining tickets available at the box office windows in the lobby of the opera house. Located at the north end of the Met lobby, these windows are staffed by fast, friendly, efficient staff who may make you wait on line, but don't put you on hold.

Purchase on the day of show.
If you're arriving at the opera house without a ticket, you still have a chance to get in. People return or exchange their seats all the time--so get on line and give it a shot. Also, you'll find conflicted audience members trying to sell off their unwanted or extra tickets in the plaza. Talk to them.