"Good Morning America" has been revealing this month the health, wardrobe and beauty secrets of the world's top supermodels so you can attempt to duplicate their effortlessly stylish looks.

Supermodel Iman appeared today on "GMA" to share her top makeup tips.

"Ladies, whatever you're doing now, put it down and put an SPF on," the 57-year-old founder and CEO of IMAN Cosmetics, Skincare and Fragrances said of her number one beauty tip. "You have to."

"All year-round, every day. My dermatologist has me on SPF 50," she said. "The sun does not discriminate."

If you want to look like Iman well into your later years, the legendary supermodel says you must treat taking care of your skin as a priority, not an afterthought.

"I'm telling you…people ask me, 'What gives your skin such a good [look] at 57?,' it's simple," she said. "It's religiously taking care of my skin."

"Like you brush your teeth twice a day, you really take care of your skin twice a day," she said. "It doesn't have to be expensive. You cleanse, moisturize and hydrate. As simple as that. Trust me, in five to 10 years you'll see a remarkable change in your face."

IMAN Cosmetics was the very first line for women of color when it was launched in 1994. The supermodel provided the following tips for how to use her makeup line:

Iman Cosmetics Skin Tone Evener BB Crème SPF 15: For healthy and radiant skin, she recommends applying the skin-tone evener with a foundation brush. You can also simply use your fingers.

Iman Cosmetics Cover Cream: Cover cream under the eyes works well, especially if it contains minerals.

Iman Cosmetics Luxury Translucent Powder: Follow up by applying this powder for a sheer, natural shine-free finish.

Iman Cosmetics St. Tropez Kit: The kit is an all-in-one palette for the entire face, comprised of warm natural tones. It contains a nude lip gloss for olive to deeper-toned skin.