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DESIGNERS' CHOICE

Shirts for spring

Calvin Klein Alpana Bawa Jean-Paul Gaultier

(CNN) -- Whether dressed-down for day or dressed-up for evening, certain designers on both sides of the Atlantic are in total agreement on what to wear for spring and summer.

There's nothing as easy as a "shirt" look when you want to appear laid-back. But for night, an elegant dress is right.

In New York, Calvin Klein says a sexy neutral "T" works alone or with a cardigan or jacket

But when it comes to evening -- Klein believes in color.

"I think some of these cotton voile pieces -- a dress, a simple shell dress -- they're great for evening," he says. "I think color because there's been lots of black at night. I think something with color just picks it up, you know, picks up your wardrobe."

Designer Patrick Robinson says the piece for this season is a blouse or a shirt.

"You can add prints into it, and it's becoming a little bit more exciting."

Knits are for evening, he says.

"Jersey dressing is still the sexiest way you can dress."

Top it off with a 'T'

DESIGNERS' CHOICE

Dresses for spring

Calvin Klein Alpana Bawa Dice Kayak

Up-and-coming designer Alpana Bawa has her finger on the pulse of what women want to wear this spring.

"The best buy for day is the T-shirt," she says. "It's very good and very casual -- anybody can wear it. It's not too expensive."

Bawa's best buy for evening: The chiffon and embroidered wrap dress.

"We showed it in red, but we're to do it in red, green, magenta and pale blue," she says.

Blouses are bountiful

In Paris, Turkish designer Dice Kayek keeps her outfits simple.

She says her collection is about an absence of color, so she concentrates on black and white.

She says they are neutral colors that work for women around the world.

For day, she recommends an organdy balloon-armed shirt.

"You can wear it with a black, nice skirt," she says.

For evening, "it's a beaded, black, square-shaped cocktail dress in crepe," Kayek says. "So you wear a nice, black dress -- don't worry because it is so simple; no one can say what is this, she's ugly or whatever... you're cool."

Jean-Paul Gaultier says the new look for day is a blouse, but it's a top that's meant to be layered.

"It's a blouse, but it's in the style of a blouson, something like that," he says. "It's a little more feminine, but with a skirt."

For both day and evening, Gaultier reinterprets the kimono.

"For night let's say, why not try the kimono," he says. "You can wear your kimono in silk with tuxedo trousers and put over it a little top in embroidery and that would be fantastic."