1. Using tanning beds. In case you haven’t heard, the World Health Organization (WHO) has classified tanning beds as a known carcinogen (i.e. cancer-causer). And if you want to accelerate the formation of wrinkles and/or get skin cancer and unsightly brown spots, using a tanning bed is the best way to do it.
2. Not using SPF daily. One unpublished study by Unilever showed that using just SPF 5 every day for five years prevented significant sun damage. Do yourself and your skin a favor and use a moisturizer with at least SPF 15. You’re moisturizing anyway, right? Most people do not apply enough sunscreen, so using an SPF of 15 should give you at least an SPF of 5.
3. Getting too much sun. 10 to 15 minutes of unprotected sun a few times a week can help your body get its vitamin D fix, but if you’re sitting outside at Starbucks for an hour a day without sunscreen, your skin will remind you years from now.
4. Using the wrong cleanser. If dryness is an issue, a foaming cleanser will only make matters worse. Two of the best cleansers for dry skin are Estée Lauder Soft Clean Tender Crème Cleanser and CeraVe hydrating cleanser. Oily types beware! A cleanser that’s too rich can send oily skins’ sebaceous glands into overdrive. The best cleanser for oily skin is a foaming cleanser such as Vichy Normaderm Deep Cleansing Gel. Combination skin types will like Paula’s Choice Hydralight One Step Facial Cleanser. If you do not know whether your skin is oily or dry, take the free quiz at www.SkinTypeSolutions.com. (Lists of cleansers that are best for each skin type can also be found in my bestselling book, The Skin Type Solution.)
5. Not using a retinoid. I am often asked “What is the best night cream to prevent aging?” In my opinion, the family of vitamin A creams known as retinoids are the best night creams and I believe that everyone over the age of 20 should be using aretinoid at night. This may help prevent aging and will smooth wrinkles you already have along with preventing acne and exfoliating the skin.
6. Over-exfoliating. How do you know how much to exfoliate? The answer is… It depends on your Baumann Skin Type. If your skin is dry, too much exfoliation strips lipids from the skin, and sensitive types can experience even more inflammation. Exfoliation is best for oily, resistant types.
7. Using daytime moisturizer if you have oily skin. If you’re on the oily side, skip the moisturizer and go straight to the sunscreen. Sunscreens have hydrating ingredients and very oily types make their own fatty acids, so they don’t need a moisturizer. (If you have dry spots, apply moisturizer only to those areas.) Everyone’s skin feels tight after cleansing, since it takes about 30 minutes for oil glands to replenish the skin—so see how your skin feels after 45 minutes and then you’ll know if you need moisturizer. Even better, take the quiz atSkinTypeSolutions.com to determine if your skin is oily.
8. Paying too much for skincare. Are expensive skincare products better? You don’t always get what you pay for. Check out this article to learn when to save and when to splurge on skin care products.
9. Not knowing your skin type. If you don’t know your Baumann Skin Type, you’re probably using the wrong products. Using the right ingredients can make a significant difference in the appearance of your skin.
10. Not getting a full-body skin exam every year. Think of this as a birthday present for your birthday suit—especially if you’ve had two or more bad sunburns in your lifetime. Find a dermatologist at www.aad.org.
for more info you can search this website
http://health.yahoo.net/experts/skintype/10-biggest-skin-mistakes-you-can-make
