Air kissing season has officially opened.

As L'Oreal Fashion Week kicks off today in an enormous white tent in Nathan Phillips Square, fashionistas across the city are puckering up for four days and nights of endless sideways smooches.

For the uninitiated, the execution of the perfect, seamless air kiss can be daunting. But this season, for the fall 2008 shows, the degree of difficulty has been taken up a notch. Because there is a strong international presence at the event and because they bring a unique set of air kissing customs, there will be many bumped heads and bruised egos. The theme of L'Oreal Fashion Week is "Wear in the World!"

With an estimated 25,000 people attending 35 fashion shows over four days, Toronto is expected to collapse into an international, air-kissing love fest. Russian designer Max Chernitov shows today. (Give him three kisses.) Elio Fiorucci of the famous Italian Fiorucci brand is the guest speaker at a Holt Renfrew cocktail party tonight. (Give him two – right then left.) And students from four Milanese fashion schools will present a show – Talenti Moda Milano – tomorrow at 4 p.m. (They'll also want two.)

With thousands of fashion players and pretenders attending runway premieres, raucous after-parties and tasteful lunches, the complex and sweetly superficial air kiss is the week's official greeting, like it or not.

Fashionistas are often ridiculed for their disingenuous, cheek-brushing air kisses. See almost any re-run of Ab-Fab. They have mastered the art of no-contact kissing. But as the international set arrives, the rules become complicated. Depending on who you're kissing, you may be required to land as many as four distinct kisses. The Spanish and Italians like two. The Dutch, Belgians, Russians and Poles will expect three. The French are all over the place and could expect two, three or even four, depending on what part of France they come from. Fashionistas from Canada exchange two kisses. Americans are often satisfied with one. And Australians will shake your hand.

It's important.

Choreograph a perfect air kiss and you're smart, worldly, confident and charismatic.

Screw up and you're an amateur.

Though it's been argued that the air kiss has primal beginnings, modern versions were popularized by socialite women who craved the intimacy of a kiss without smudging their makeup. Over the years the air kiss has been caricatured as insincere – "a snobby kind of mannerism," according to etiquette know-it-all Letitia Baldridge.

Like air hockey and air guitars, air kisses are not the real thing.

Explains Susie Sheffman, fashion director of Fashion magazine and reluctant air kisser, "I'm never the instigator. I think it's something the Europeans do best. I hate it when there's that awkward hesitation. And when your noses bump – that's the worst."

Fashion watcher Victoria Webster, 32, says you've got to be nimble. Never hesitate, she says.

Decide in advance who you are going to kiss, instructs Webster. There is a pecking order with designers, fashion editors, photographers and interns. "If it's your boss or an elder you should hang back. Accept that some people are more reserved. The French kiss everyone. We don't."

But once you've leaned in you have to finish the job, she says, no matter how awkward it becomes. A loose hug is only a default position. Body language experts tell their clients to give someone the "heads-up" if you want to give them an air kiss. Approach with your arms open and grasp their hands or arms.

Gently brush together cheek-to-cheek, first right, then left. Be sure you make contact, though. And never make the "mwah-mwah" sound. You'll be sent home.

We all know it's fake, says wardrobe stylist Georgia Groom. But you've got to put some feeling into it, she says.

Webster also admits that at large events she often suffers from air kissing fatigue.

"Enough already."

Barb Atkin, vice-president of fashion direction for Holt Renfrew, is declaring her own personal moratorium on air kissing during L'Oreal Fashion Week.

"I have been travelling since Jan. 9. I'm really sick," says Atkin, worried she may pass some flu-like bug.

"I think the Japanese have it right. They cherish their space away from other people.