You might not think you’re so pretty, but you’re wrong! In fact, all girls are beautiful. But if you’re going around feeling and acting all negative, well, few people will be able to actually see the awesome bag of gorgeous you’re packing. It’s like having a foggy downer cloud hovering all around you that obscures your true beauty.

Luckily, if you know how to feel good in your own skin, you’ll put off an amazing energy that is incredibly attractive. Give these beauty tips a try:

Bare Your Teeth
As in, smile! Nothing radiates your inner beauty like a big, genuine grin on your face. Even if you have a mouth full of braces, spread your happy vibes all over the place. (Hey, that rhymes!)

Not feeling it so much? Smile anyway: Studies show that smiling releases your body’s feel-good chemicals, called endorphins and serotonin, which will in turn make you happy. So even if you’re feeling down, don’t frown (on a rhyming roll!). Um, can you say “Cheese”?

Stand up Straight
When you slouch, you send a message that warns, “Back off -- I don’t feel so great about myself.” But when you pull your shoulders back and straighten out your stance, you command a whole lotta positive attention. Simply strut some non-arrogant but rock-solid confidence, and you will turn heads.

Be Healthy
A healthy body is fit and well-nourished. So do not -- we repeat, do not -- cut out any meals or work out like crazy to be ridiculously thin. Instead, eat lots of good-for-you foods, such as fruits, veggies, whole grains and low-fat proteins. And do fun things for exercise, like sports and roller skating. Your body will be in its best form ... and as an added bonus, your skin will emit a very radiant glow. You go!

Love Yourself
Here’s the thing -- if you don’t think you’re fabulous, the world will reflect that right back at you. So first thing every morning when you’re getting ready for school, look in the mirror, give yourself a big smile, and say, “Hello, gorgeous!”

This does not mean that you can act like you’re all better than everyone else. You’re not -- but remember, every girl is pretty in her own unique way. And that goes for you, too! Don’t ever forget it, OK?

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Scientists study some pretty cool stuff. Seriously -- they’ve even figured out what foods have the power to make you feel happier when you eat ’em. Read on to find out what packs the biggest mood-boosting punch -- along with yummy recipes to work more of them into your routine.

The Food: Walnuts
Whether homework overload or fights with your mom have been plucking your nerves, walnuts are your new BFF. When people snack on a few of these nuts each day, their bods actually get better at coping with stress.
The Fix: Sprinkle chopped walnuts on top of your cereal in the a.m., or use them to add crunch to ice cream or fro-yo.

The Food: Bell Peppers
These veggies are packed with vitamin C, which is shown to give a serious pick-me-up. Make sure to stick with the red and yellow ones, though -- green peppers don’t come with as much of the feel-good nutrient.
The Fix: Cut peppers into strips and dip them in your favorite hummus or yogurt dip.

The Food: Strawberries
These fruity kisses just happen to be loaded with a little something called folate, which helps your bod produce more of the blues-beating hormone serotonin.
The Fix: Treat yourself to a yummy smoothie by blending frozen strawberries with milk and a banana.

The Food: Toast
One whiff of this bad boy gets you feeling zen -- pronto. According to a recent study, the scent of toast makes people feel happy instantly!
The Fix: Skip dessert tonight. Instead, have a slice of toast with a chocolate-hazelnut spread.

The Food: Salmon
Salmon is one of the best sources of omega-3 fatty acid, a type of fat that’s actually good for you. Why? It boosts brain power and fights off depression.
The Fix: Make a salmon-salad wrap by mixing a can of drained salmon with some low-fat mayo and a bit of chopped celery, then roll it up in a flour tortilla.

The Food: Water
OK, so H2O isn’t technically a food -- but it can help perk up your day! Since dehydration causes fatigue and all-around crankiness, loading up on the clear liquid helps you avoid a case of the blahs.
The Fix: Throw a few fresh mint leaves in a glass of ice water and add a couple of squirts of lime juice for something you’ll love sipping all day long.

The Food: Chocolate
It’s true -- the sweet stuff really can reduce stress! The catch: It’s gotta be dark chocolate. Also, you probably want to stick to 1 ounce a day so you don’t overload on sugar.
The Fix: Melt down a bar in the microwave, stirring every 30 seconds until smooth. Then dip pretzels, marshmallows -- whatever! -- and let them sit on wax paper until hardened.

Being stressed makes everything harder: You’re less likely to focus in class, more likely to fight with your BFF, and you might even get sick. To get your carefree self back, here are some cool ways to help you relax. Some of them might sound wacky, but they work! So get ready to try something new ... and ditch the stressed-out you.

Be a Poser
Girls who do yoga feel strong, focused and self-confident. Yoga is all about being kind to yourself. It helps you live “in the moment” instead of dwelling on yesterday (ugh, you tripped in the cafeteria) or tomorrow (big algebra test coming up). Plus, we love all those cute animal names for poses, like Camel, Monkey and Downward-facing Dog. Ready to strike a pose? Grab a DVD or search “yoga for kids” online. You’ll be stretching your way to serenity in no time.

Color Your World
Ever hear of looking at life through “rose-colored glasses”? They really exist! Some people use color therapy (treatment with tinted lenses or lights) to ward off depression. You don’t have to go that far, but remember that your environment can affect your emotions. Blue is soothing, pink is playful and yellow is energizing. So whether you’re picking an outfit or decorating your room, surround yourself with happy hues.

Clear Your Head
Smart girls like you have lots of “chatter” going on in their brains. Try meditating to calm your mind. It can be as simple as closing your eyes, breathing deeply and repeating a single word for a few minutes. (Pick a word like “happiness” and not your crush’s name so you don’t defeat the purpose!) Or lie on the floor, turn on some classical music or nature sounds, and imagine the most beautiful place you can think of.

Lighten up
Some people are extra-sensitive to the changing of the seasons, especially when it’s dark and dreary outside. If that’s you, you might need more light in your life. Be sure to spend time outside every day: Walk to school, shovel snow (your parents will love it) or ride your bike. Bonus: Aerobic exercise, whether it’s indoors or out, is a proven stress reducer!

Be Nosy
Some smells can trigger a positive response in your brain, so try aromatherapy! Scents like lavender, cinnamon and ylang-ylang could help you relax and sleep better. On the other hand, grapefruit and peppermint will wake you up. Instead of buying essential oils, which can be potent and expensive, go for scented candles and bath products. Or you can sip a cup of chamomile tea before bed. Sweet dreams!

If you’re trying to get your tan on like the guidettes from MTV’s “Jersey Shore,” you may want to think twice. Having that summer glow might look and feel healthy … but it’s not! According to the Skin Cancer Foundation, 90 percent of all skin cancer is caused by sun exposure. Ouch!

“Do I really need to worry about that stuff now? I’m just a kid.”
Harsh but true: Just one severe childhood sunburn doubles the chance of developing skin cancer later in life. Kids with fair skin are at highest risk, but even dark-skinned children need sun protection. “Fewer than one-third of children between ages 8 and 11 wear sunscreen,” says the Skin Cancer Foundation’s president. “Parents need to teach children from an early age how to be sun-safe and reduce their risk of skin cancer.”

“Aren’t tanning beds better for your skin than direct sunlight?”
No way! It’s a total myth that tanning beds aren’t bad for your skin. They produce the same skin-damaging ultraviolet rays as the sun. Says the Skin Cancer Foundation: “Study after study has shown that sun bed tanning increases the risk of skin cancer.”

“I really hate my pale complexion! Isn’t there a safe way to tan?”
Why not embrace your natural skin tone? Look at yourself as creamy porcelain (like Scarlett Johansson!), not pale. But if you’re bent on getting a sun-kissed look, use self-tanning lotion or bronzer. They’re way safer than sitting outside, but it’ll give you the same results (and faster). Some tanning salons also offer spray-tan booths if you want to get total-body coverage. (These can be pricey but are a safe alternative to UV rays.)

“Do I need sunscreen even if I’m wearing a hat and sunglasses?”
Brimmed hats and UV-blocking glasses do provide some protection … and are summer-stylin’ accessories! Dark or bright-colored clothes are good too. Still, don’t skip the sunscreen. Go for a water-resistant product with an SPF 15 or higher. Put on a thick layer a half-hour before going outside; reapply every two hours and after swimming or sweating. And don’t forget easy-to-miss spots such as ears, neck and feet!

“Can’t I just sit under a tree or umbrella? I like the shade.”
Like wearing hats and glasses, sitting in the shade is great for getting extra protection from the sun’s harmful rays. But you can’t rely on that alone since the sun reflects off surfaces -- so slather on that sunscreen.

“I hate sunscreen because it gets in my eyes and burns. Help!”
Try a sunscreen that’s made specifically for babies (really!). These products are tear-free and not as harsh as other products, but they’re just as effective as regular lotions. Bonus: They’re perfect if your regular sunscreen causes breakouts or “backne.”

Puberty brings physical changes that might temporarily affect your game. But don’t go from player to spectator! Just change your strategy.

“I have a killer volleyball serve, but I also have killer cramps. Ugh.”
Cramps can really cramp your style. But did you know that exercise can help alleviate cramps? Before hitting the court, talk to your mom or doctor about over-the-counter meds like ibuprofen and acetaminophen, which are known to take the edge off the pain. A heating pad or hot water bottle can help too. If your cramps are unbearable, be honest with yourself and your coach -- you won’t be much of an asset if you’re in excruciating pain.

“Help! My boobs seem to be running their own race during track and field.”
It’s hard to focus on mastering your 100-meter sprint when your boobs are bouncing. A good sports bra is crucial, as breast tissue is sensitive -- especially during puberty. A sports bra not only keeps breasts contained, but it also provides coverage to shake self-consciousness. Enlist the help of your mom or big sis, and get measured at a professional fitting. A wrong-size bra can be more distracting than going braless.

“My swim meet is next week, and my period is due. Will I be able to compete?”
In some sports, using a tampon versus a pad is a personal decision. Many maxi-pads now come in slender versions, and some have “wings” that secure them to undies. But swimmers have no choice: Fact is, if you’re not willing to use a tampon, you won’t be swimming in the meet. It’s also difficult for dancers, skaters and cheerleaders to wear pads -- hello, leotards! If you’ve never used a tampon, simple instructions are included in the box to get you started. Or run the issue by your mom, aunt, school nurse or gynecologist.

“My gymnastics floor routine has been tripping me up ever since a growth spurt.”
When you grow several inches in a short time, it can throw you off. And because your limbs grow faster than your trunk, it’s not unusual to feel like you’re losing a little coordination. Weight gain is also a very normal part of growing up, so don’t freak if you’re a bit thicker in your upper arms, thighs, hips and back. If this is you, embrace your new curviness!