Rev up your rep: no doubt, you're already fab. But there's always room for an awesome image-bustin' change for the better. This school year, make that leap!

Maybe you want to peel away the shyness and suddenly reveal the girl who can chat up anyone (and has tons of new buds to prove it). Or perhaps you want a radical Princess Diaries-style makeover or to blow everybody's minds by switching up your major activity (from soccer star to student council prez?). Do you want your teachers or 'rents to see you differently? Adios, chica whose dog ate her homework; hello, honor-roll student.

Whatever change-a-roo you want to do, there are 10 no-fail secrets to becoming a great new gal--while sticking to the true-blue you. Read on while GL spills all you ever needed to know about a successful image overhaul....

Rep Revvin' Rule #1

MAKE THAT CHANGE FOR YOU

Make a key change only when it feels completely comfy and right. Tons of girls make the mistake of going against their instincts to impress others, and that never works.

Say your crush digs how Mary-Kate has gone hippie. Your style is preppy, but you dash out to buy some tie-dyed skirts. But if boho isn't your vibe, you're going to feel silly and icky wearing them, and that's just plain unattractive.

Changing up to please someone else is always a no-no. Your BFF Jaclyn spends a whole 10 minutes in advanced geometry before realizing she's in over her head? She's switching to way-easier algebra and wants you to switch too. You hate to let your girl down, but you're proud of your "math nerd" side--you get A's solving even the toughest probs. If you change classes, you're selling yourself short for Jaclyn's benefit. You know deep-down what's good for you.

Rep Revvin' Rule #2

IT'S ALL IN THE DETAILS

You can't just flip a switch on your image--you've gotta commit to the work it takes to make cool stuff happen. Serious effort is about paying attention to the nitty-gritty. Want to expand on your super-brainiac rep by making the cheering squad? Then get down to biz and start lovin' those backflips--you need to practice tons to ace tryouts.

Break things into do-able steps. To turn your French grade around, focus on learning one new word at a time rather than spazzing at the thought of mastering a whole section. Slow down, and concentrate on the details of any change. One step at a time, sister.

Rep Revvin' Rule #3

FAKE IT 'TIL YA MAKE IT

Tossing the baggy jeans in favor of super-fem skirts? Breaking news: You might feel a little uncomfortable sporting your new look at first. What to do? Act confident decked out in those gorge new clothes and, soon, you'll feel that way.

It's normal to feel a bit weird sportin' a new image. You're wondering how everybody else is gonna react to the new you. So stand up straight, check yourself in the mirror, and admit, "I look terrific!" Then walk proud. Look people in the eye, smile, and feel mighty swell about yourself. If you're mega-positive, others should absorb your good energy.

Rep Revvin' Rule #4

RIDE OUT REACTION

Be prepared for a big ol' range of reactions to your change. You might get tons of support from the crew, and even snaps from girls you barely know. Or you could get loads of jealous comments and disses. Yep, this can be a total shock. When you take control of your life in a major way, other girls may find it threatening. They take it personally that you've done something positive, and they haven't. Small-minded and yucky? For sure. But don't let it bum you out.

Ride out bad reactions--they're probably just a temporary hassle. If your BFF is giving you an occasional dig about your landing the lead in the school play, chances are good she's gonna come to her senses and feel bad for giving you weird vibes. Anyone worth having in your airspace is, in the end, gonna support you. Anyone who keeps the cutting comments coming isn't really a friend--so losing her isn't losing much.

Rep Revvin' Rule #5

DON'T PREACH

Once you've lost 20 pounds, it can be tempting to urge your sis to give up her Fritos for carrot sticks. Don't go there. The best way to inspire is by living your life, not by telling others how to live theirs. This is not to say, though, you can't share secrets about how you met your goal--as long as you're asked.

Rep Revvin' Rule #6

DON'T BE SO HARD ON YOURSELF

Don't hold yourself to impossible standards. Let's say you've brought your GPA way up. The trick is not to be so rigid that you say, "I can never get a B again." You've got to cut yourself some slack. Keep your study habits sharp, and do your best. But no need to live on red alert, where one little slip-up (so you tanked the pop quiz) might make you give up on the change. Relax, and just keep movin' forward.

Rep Revvin' Rule #7

MAINTAIN, NO PAIN

Changes take time to blossom into full-blown blooms. The best way to stay psyched is to keep a reminder of the way things were before. Looking at your old report card with its C's and D's will keep you from getting lazy. Plus, it'll give you an instant rush of good feelings about the improvements you've made.

Rep Revvin' Rule #8

TAKE A COMPLIMENT

Groovy feedback makes some folks veeeeeery uneasy. You deserve props, though! Think of the hard work, strategy and smart planning that goes into a rep adjustment--getting the swim coach to take you seriously when you'd previously only played b-ball was not exactly cake. So when you win your first backstroke race, you deserve to enjoy it.

When someone praises your newfound accomplishments, don't turn red and mumble, "No biggie." Instead, look 'em straight in the eye, smile, and say, "Thanks, you just made my day!" Then savor the moment. You've so earned it.

Rep Revvin' Rule #9

FEEL FREE TO CHANGE BACK

If you've taken a stab at a major new activity and you hate it--even if you're good at it--you don't have to stick with it. Think quitting is the ultimate image-buster? Afraid people will see you as a fickle loser with no staying power? No way! You'll look like someone who gave a new activity an honest shot and is smart enough to know it isn't your thing.

Makes a lot of sense, but you know what? Many girls are willing to suffer just because they're worried about what other people will say if they bag it. That's not only lame, it's a colossal waste of time and energy--don't do it.

Rep Revvin' Rule #10

BE REAL

It's not just what you do--it's also about how you make people feel. The girls with the most respectable reputations are the ones who are for-real. Rockin' reps are earned. And the best way you can rake in yours is to be kind, warm and honest to everybody you know, every single day. What's more admirable? Not much!