Stunning beauty Kate Upton has quickly become one of the most high-profile American supermodels working today, and she shares her tips for looking one's best in the latest issue of Cosmopolitan.

The 20-year-old blonde bombshell covers Cosmo's November edition, and she says looking sexy is simple.

"To me, what's sexy is when you look like you're having a good time. That, and when you look effortless and have messy hair," Upton told the magazine.

Upton looks effortless herself in the photos from the magazine shoot, which feature her wearing a casual black top, denim shorts and cowboy boots while she sits in the bed of a truck filled with hay.

The model said the photos aren't far from the real her, as she can be a country girl when she's not glammed up.

"I'm a little bit of a mix - a girly girl and a tomboy," she said. "When I'm in a city, I'm girly. But when I'm around a barn, I turn into a tomboy."

She also offered some tips to men who are trying to pick up a beautiful woman.

"All pickup lines are horrible - none of them work," Upton said. "You just walk up ... make a fool of yourself."

Upton has been expanding her body of work lately. Typically known for stripped-down photo shoots in bikinis or lingerie, she recently appeared on the cover of high fashion French magazine Jalouse, and she was almost completely covered up.

"It's funny, fashion shoots do not resemble at all swimwear shoots," she said. "Pose, I can do, but customer expectations are not the same. Everyone acts differently on the set. The bikini photos are for any American home. Fashion is for a unique group."

Upton also detailed the differences between various parts of the modeling industry.

"The world of fashion is a clique," she said. "What matters is not to be pretty, but different, to reunite all the characteristics of perfection, but in a staggered manner. This is what they want."

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