From left, Alexander McQueen, Rochas, Louis Vuitton, Lanvin, Balenciaga

(7) You’ll Put on a Pump.
The flats you saw during the New York collections are fine for trekking up Madison Avenue, but if you’re strolling St.-Honoré, consider a heel. Designers like Alber Elbaz at Lanvin, who’s made a strenuous case in seasons past for round, girlish flats, added inches this time; Marc Jacobs kept things low to the ground for his eponymous collection but went far more femme fatale at Louis Vuitton.

From left, Louis Vuitton, Undercover, Junya Watanabe, Valentino, Hermes

(8) You’ll Figure Out Your Hat Size.
And work on your angle. At Louis Vuitton, the toppers were extra-large; at Undercover, they were all fedoras. Valentino and Hermès amped up the newsboy cap that’s been so street-trendy in New York. The overall effect? A sexy, mysterious addition to the menswear trend.