We all know her: The woman who has the kind of amazing, perfect skin (seriously, where are her wrinkles?) that makes you wonder if she's resorted to witchcraft, or just has a really good dermatologist. Turns out, her face is full of secrets -- and we're here to spill them. We chatted with women of all ages who have the glowy skin of our dreams to see what steps keep their skin flawless.

"So many times I say to a patient, 'You have such beautiful skin,' and they'll say, 'Well, my grandmother at age 90 had no wrinkles,'" says Debra Jaliman, MD. "But that doesn't mean if you were dealt a bad hand in the genetics department that you can't overcome it."

Here, the eight steps women with perfect skin always do -- try them and say hello to radiant skin.

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You wouldn't apply the same lotion to your face as you would your body, but women with perfect skin take it a step further: They treat areas of their face differently, depending on their needs, as opposed to slathering every serum, night cream and moisturizer over their entire visage.

For instance, Susan, in her 60s, uses her sumptuous night cream everywhere but her forehead, where she tends to get oily. Dawn, from New York, applies a pigmentation serum only to her freckles, and her face oil only around the periphery of her face, and her neck and chest.

Why you should try it: According to Jaliman, different areas of your skin call for different types of care. Some areas of your face are thicker-skinned (like your forehead) while other areas are more sensitive (like your eye area) If you have combination skin, use a toner with salicylic or glycolic acid only on your oily t-zone. If you have lines on your forehead, spot-treat them with retinol, rather than applying it all over and risking unnecessary irritation.

Image via Hello Beauty Blog

Much in the way you wouldn't leave the house without brushing your teeth, these women slather on sunscreen every morning, without fail, even if they're simply en route to the office. And, no, a BB cream with SPF 15 doesn't count.

Even if their day cream and foundation have SPF protection, they still layer on a dedicated sunscreen (We love Dermalogica Pure Light SPF 50, $62 for its quick absorbency and matte finish).

When outdoors for extended periods of time, our perfect-skinned women are just as diligent about reapplication -- every two hours as recommended. One of our favorite ways to reapply without messing up makeup: using a mineral sunscreen powder that we can dust on. Try: Colorescience Sunforgettable SPF 30 Mineral Powder Sun Protection, $50.

Why you should try it: "Every day, rain or shine, it's important to use an SPF 30 sunscreen with broad spectrum protection," says Jaliman. She says there have been twin studies that show that the twin who wore sunscreen looked 10-20 years younger than the twin who did not wear sunscreen.

Jaliman prefers physical sunscreens with a high concentration of zinc oxide, because they're soothing to the skin and don't cause irritation. If you're going to be sweating outside, choose a water-resistant formula that's good for at least 80 minutes.

Image via Vayzo

Many are diligent about adding a layer of antioxidants under their SPF to further prevent free radical damage (a favorite: SkinCeuticals CE Ferulic). Dawn uses them diligently under her sunscreen, even when going for a run (as a New Yorker, she's exposed to a lot of pollution -- read more about the effects of pollution on your skin here).

Why you should try it: Antioxidants combat free-radical damage from cigarette smoke, pollution, UV rays and stress, explains Jaliman. But how, exactly, do free radicals mess with your skin? They damage collagen and elastin tissue, resulting in -- you guessed it -- wrinkles, she says.

While the makeup routines of our interviewees varied, they all have one thing in common: They remove every speck of it every single night.

To wash away every last trace of dirt, pollution and makeup from the day, do as the flawlessly skinned (and Japanese) do, and double cleanse. Carol, 24, always uses an oil cleanser to remove her makeup before washing with her regular cleanser to get her face squeaky-clean and ensure no pore-clogging makeup is left. Bonus points if you use a sonic cleansing brush, like the classic Clarisonic, a product many respondees are fans of.

Why you should try it: Remember those pesky free radicals? If you don't thoroughly wash your face at night, not only are you leaving oil-clogging makeup behind, you're also leaving wrinkle-causing pollution all over your face. In the short term, going to bed without washing your face can lead to breakouts and uneven skin tone; in the long term, it leads to free radical damage (AKA wrinkles and dullness).