Do you have a need to be the center of attention, but don't know HOW to get it? It actually is quite easy, but you have to be ready to have all eyes on you! It just takes a little style, a big smile, and some confidence!

Wear truly fabulous clothing. Check Teen Vogue, Cosmogirl, Glamour and other high-fashion mags for inspiration. Try to find outfits that look similar to those you've seen in those magazines and add a personal touch. For example, if you want a romantic look for a change as you normally prefer rock-chick style, add jeans with studs. Find a fashion idol such as Peaches Geldorf for the britain-rocks-style, Sienna Miller for bohemian and vintage, Ashley Tisdale for the happy-go-lucky-LA-look :)Think of matching colours (for example: blue and turquoise, red and brown, orange and yellow, black and white and so on), matching styles (Never mix emo with preppy. It looks ridiculous!) and all that stuff.
Be a positive person. You don't want to seem as if you are always complaining about something. Show people that you love life! Smile and embrace the world every day :) You gotta be thankful for the life god gave you, so use your chance and live it the way you like it! Have fun and enjoy it! Being fabulous is also about being unique, and that shows through your lifestyle especially!
If you wish to talk to someone whom you do not know, do it through a compliment or a statement about something you have in common (i.e. "This gym class sucks!" not "I read your facebook profile and I found out that you love Ugly Betty! I do too!") You may build off of this, slowly. Try: "Where'd you get this skirt? It looks really cute!") Or for a boy (flirtatious): "Hey, you do some sports? Those muscles are awesome!"
Be sure to keep yourself looking lovely! Remember to bathe, brush your teeth, etc. It's VERY important! Also, don't forget to put a little make up on! But less is more, so it's best to just keep it natural and wear foundation to cover imperfections, a coat of mascara before curling lashes and a pink lipgloss slightly darker than your lips.
Get involved! It's good to be well rounded. Join clubs you're interested in. You can do sports, arts, design, photography, literature and many others! There are so many opportunities to style up your social life. Go to every party you're invited to and show off you're open and nice! And of course, totally fabulous!
Be confident! Don't be ashamed of your body. If it bothers you try eating healthier and working out. Go through school with your head held high and be proud of what you got! Always think of yourself as unique, smart and beautiful. But don't be nasty or arrogant. People hate that.
Consider reading some of the popular style books about being fabulous, like, Fabulosity: What It Is & How to Get It. by Kimora Lee Simmons. Style, Beauty, Trimness: The art of easily being stylish, attractive and well turned out. by Nancy Marie. or Style A to Zoe: The Art of Fashion, Beauty, & Everything Glamour by Rachel Zoe.

Have good posture.
Get decent enough grades that you will be able to do the career of your choice.
Be confident, but realistic.

Don't try too hard. It will be much easier to be "fabulous" if you act normal. Be yourself!