If you have dry, sensitive skin, you may be wondering if you're using the right moisturizer, or if you should switch to an oil, or a balm—or maybe a serum? And what's the best way to exfoliate without causing more irritation? The editors of Goop have you covered with their new Goop Clean Beauty ($30, amazon.com), a thorough guide to looking naturally gorgeous (and the first book from Gwyneth Paltrow's lifestyle brand). "Whether you suffer seasonally or constantly, and whether the problem is severe or mild, arriving at the ultimate regimen that keeps your skin supple, dewy, and comfortable is an achievable goal for most people," the editors write. But because the causes of dryness and irritation can be so varied, finding the right products for your skin takes some tinkering. In the excerpt below, they outline the essentials elements of a healthy hydration routine, which can be tailored to your own preferences and sensitivities:

CLEANSE

How you cleanse your skin—both face and body—is an essential factor to look at if you are struggling with dry or sensitive skin. Pretty much anything that foams or lathers is your enemy. Lather = detergent, in most cases. Conventional “moisturizing” body washes, for example, combine moisturizing ingredients with detergents (not to mention perfumes, which can further irritate and dehydrate)—which can spell serious trouble for dry skin. Consider oil, cream, or balm cleansers (natural, clean ones are much more likely to include only moisturizing ingredients as opposed to fillers and texturizers), and consider cleansing less. Your skin isn’t dirty when you wake up in the morning—so don’t bother disrupting it with cleansing. If you must cleanse in the morning, finish immediately with an oil or moisturizer. In the shower, cleansing oils or creams are ideal, and a super-gentle (the gentle is important), very oily scrub can lightly exfoliate and moisturize all at once.

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MOISTURIZE

How thick a cream or lotion is often indicates how moisturizing it is. But what you see isn’t always what you get. Conventional moisturizers can appear thick, but much of that richness might be added fillers and texturizers. Silicones are particularly deceptive, they add nothing to the actual hydrating power of a moisturizer, but are used to make products feel more moisturizing, blend-able, and comforting. Another extremely common texture-enhancer, propylene glycol (a.k.a. antifreeze), makes products feel softer and gentler, but does nothing to actually nourish or help skin. Conversely, there are ultra-hydrating serums that feel like practically nothing on the skin. Still, in general and especially when you’re working with clean, nontoxic products, thicker is a fairly reliable indication of more moisturizing power.

Applying moisturizers—or any products, really—when your skin is wet is a good idea for two reasons, the obvious being that it seals in the water that’s on your skin. But the more important aspect is that wet skin is more porous, so treatment ingredients—in this case, hydrators—can penetrate into deeper layers of the skin, where they can do the most good.

In addition to moisturizers, there are a handful of other classes of products that deliver the same results. Below we outline the philosophy behind using balms, oils, cream, lotions, and serums:

Why use a balm

The thickest, most skin-coddling, nourishing option in moisturizing, your average balm is not something you’re going to want to put on under makeup: A good one is thick, occlusive, and super-healing. Most balms are nicely multipurpose and great on skin, but also lips, and on dry or rough spots all over the body. You can also use them over sunblock in extreme weather situations like skiing.

Why use an oil

Oils are the original moisturizer; women have been using them for centuries. They vary in texture, depending on the type of oil, so definitely experiment with a few before deciding yea or nay. You can use an oil just like a regular moisturizer, though they generally take a few minutes to sink in enough to apply makeup over. Apply face and/or body oils as often as your skin seems to like. You can use body oil in your bath instead of products labeled “bath oil,” which, especially in the world of conventional beauty products, mix oil with detergents to make the oil disperse evenly. (Yes, this is as drying as it sounds.) The general rule of thumb: If it foams, it’s seriously no good for dry skin. Body oil—100% oil—will leave your tub a little slippery (and be careful, as the number 1 place household accidents occur is the bathroom), but will also leave itself on your skin, gloriously if unevenly. Because hot baths (who, except someone in an extremely hot climate, wants to take the oft-recommended tepid bath?) are drying, using body oil in the tub can help you retain moisture.

The other thing oils are amazing for is, oddly, refreshing makeup. You know that 4 p.m. slump when your skin looks faded and tired and you feel like you should re-do your makeup? Smooth a little face oil onto your fingertips and pat onto your skin over makeup—it will enliven your face and freshen your whole look without requiring more layers of makeup.

Why use a cream 

One of the serious advantages of a nice, rich face or body cream is the texture. A cream distributes moisture more evenly than other products and it lasts longer on the skin than your average oil or even balm. Creams are also fantastic for sealing in an oil or a serum.

Why use a lotion 

Some people don’t like the feeling of a heavy cream on their faces; lotions are generally lighter. They can be a little less moisturizing, but not necessarily. The key is, if you love a lighter texture, pick a lotion and use it as often as necessary. If you enjoy the experience, you’ll stick to it.

Why use a serum

The light texture of most serums means that, for the most part, they’re less moisturizing. While there are exceptions to that rule, think of most serums as the best way to deliver active ingredients (i.e., brighteners or firming or anti-wrinkle ingredients). Most people with any sort of dry skin issue are going to want to layer a moisturizer or oil over a serum.

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LAYER

Smoothing on product after product can leave you with irritated skin and/or product piled up on your skin in weird clumps. But done judiciously, it’s a great way to A) get more moisture into skin, and B) treat dry skin with anti-aging or anti-acne ingredients without over-drying. Keep the number of products as minimal as possible, and leave time—a few minutes at least—between your layers, so each product has an opportunity to sink into your skin.

Dermatologists advise applying sunblock first. Always use a physical/mineral sunblock as opposed to chemical sunscreens, even in gentle-looking “daily moisturizers.” Chemical sunscreens are some of the most irritating compounds we put on our skin; they’re right up there with fragrances, and sometimes even worse. (They also quickly degrade in sunlight, rendering them useless after a few hours.) The added benefit of physical sunblock is that because of the minerals they’re made with, they’re actually soothing to reactive skin: As you’re taking that extra minute to rub in the extra whiteness of a sunblock, consider that the same stuff that makes it hard to rub in also soothes severe skin irritations like diaper rash; it’s also the same stuff cosmetic companies mix into foundations to “blur” and minimize skin imperfections.

After sunblock, assess whether you need more moisture (most people with dry or sensitive skin will, but know that even a dry-feeling sunblock does have a skin-barrier-reinforcing, hydrating effect). For some, an oil will feel great, others might love a cream, still others might need only a serum (and for those who prefer to apply serum or moisturizer first, wait, then apply sunblock, it’s probably not the worst idea in the world to really deliver the serum deep, unless you’re headed for a day at the beach).

Remember that any tinted moisturizer/CC or BB cream/foundation is essentially another layer: It too has a protective, mildly hydrating effect. If you’re using a product made with a physical sunblock and you like to use it all over your face, it’s probably a good-enough sunblock layer on its own for a day when you’re going to the office or otherwise mostly inside. For an outside day or if you’re always by a big window, do both sunblock and whatever foundation-ish product you like.

INTERNAL SUPPLEMENTS

Supplementing with omega-rich oils—from salmon or cod-liver to flaxseed or evening primrose —can make a serious difference for people with dry skin. As with everything else, the only way to know is to try. Keep oils fresh in the refrigerator, and be sure to get them—particularly salmon-oil capsules—from a reputable provider: New studies have shown that rancid oils, particularly fish oils, can actually cause inflammation—the reverse of what you’re trying to do. Some people have also had good results with anti-allergy compounds like quercetin.

EXFOLIATE

People with irritable or dry skin often avoid exfo­liating, because it seems like it would worsen the problem. Exfoliating too much will absolutely dry skin, and can seriously disrupt the protective man­tle of the skin and compromise its barrier function. But the right amount of exfoliation makes skin function better all over, plus it allows treatment ingredients to get further into skin.

Scrubs made with lots of oils and emollients feel especially good if your skin is dry; you have to watch your step in the shower, but you’ll often emerge fully moisturized, without having to apply lotion or cream after. At the very least, they give you a head start in terms of layering on product, and sealing in moisture.

Chemical exfoliants—AHAs, BHAs, and plant enzymes like papaya—are often the best solution for dry or irritation-prone skin, but use them extremely cautiously, because their strength varies widely. AHAs were actually initially developed to treat an extreme dry skin condition called ichthyosis; their exfoliating qualities allow treatment to penetrate and smooth the surface in a way that can help treat irritation, too. But a too-harsh AHA on dry or irritated skin can compound the problem; so again, proceed with caution and consult a dermatologist if need be.

Excerpted from the book GOOP CLEAN BEAUTY by The Editors of goop. Copyright 2016 by Goop, Inc. Reprinted with permission of Grand Central Life & Style. All rights reserved.