Sipping through a straw 1
Sipping through a straw may prevent teeth staining in some cases, but the puckering can also cause lines around the lips. If done regularly, it can also strain the skin in that area, causing deep creases on the side of your mouth.
Cleansing too vigorously 2
Washing your face regularly is crucial, but if you're overzealous with your cleansing, it could strip your skins of the oils it needs to stay smooth. So make sure you get the right kind of cleanser for your skin and be gentle!
Moisturizing the wrong way 3
Applying moisturizers and lotions from top to bottom can make the skin sag since you're pulling it down. Try starting from the bottom up and make sure you're rubbing in gently.
Too much sun 5
OK, so you all know this one, but it's summer so it's worth reiterating. SUNSCREEN, SUNSCREEN, SUNSCREEN. Even spending just a few minutes outside in the hot sun without applying it can wreak havon on your skin, from aging and wrinkles to much worse.