1) Do something awful to get your parents to disown you. But don't go crazy. Just something they'd hate, not something the police force and/or government could potentially hate. This way, you're not a criminal, orphan, or murderer, you just don't have a legal guardian.
2) Run off to LA for the summer. Stage a scene in which some celebrity could potentially die but jump in at the last second to save their life. Be sure you don't get too creative, though. Make it so that you can easily save them without putting your life in too much danger. And although I assume this is self-explanatory, I'll clarify regardless: Don't make it look like the incident was caused by you, just prevented by you. Otherwise, you're a criminal. And that's not what we want to accomplish.
(Also, Celebrity-wise, I'd say Robert Downey Jr., James Marsden, or Morgan Freeman but that's just me... it'd probably be best to choose someone more iconic like Zac Efron but married and adultish, so more like Brad Pitt or Tom Hanks. Or just go with Robert Downey Jr. if you can. I absolutely adore him. But then again, he might be intimidating and/or just plain frightening in person. Maybe John Cusack? Leonardo DiCaprio? Eh, nevermind, just go for someone famous, cool and preferably somewhat sane since all celebrities are out of their minds. Plus, aim for someone ridiculously attractive.)
3) After you save said celebrity from a near death experience, they'll probably owe you. Big time. So they'll take you out to dinner or whatever. Here's where you really need to make a good impression. You don't need to jump right into father-daughter relationship status yet, but be likeable enough to get invited to do something else with the celebrity you selected. As the two of you grow closer over the course of the summer, the required father-daughter relationship will soon begin to form.
4) On any particular outing with your celebrity, mention how your parents disowned you. Be sure that your celebrity really cares about you at this point, otherwise you'll come across as dangerous and a little intimidating and possibly image damaging. Cry a bit and tell your celebrity about how you messed up. Mention that your parents overreacted, but make it clear you're remorseful, sad, and longing for a Dad. Haha, that rhymes! :)
5) As the summer continues, your celebrity will grow so close to you that he'll want to fill the void in your heart by becoming your father. Since he's wealthy, he'll be able to buy you a house near your old school so to not make you abandon your old friends. And if he doesn't, he'll at least put you in a town/city with a decent school system, preferably not in LA (where knowing a celebrity is less special that knowing one in, say, Nebraska).
6) Don't brag when you get back to school (or start at your new one). No one needs to know who your father if. Granted, if you make new friends and you don't want to lose them you can trust them. And of course, if you're staying at your old school, be sure to keep your old friends by telling them about your summer so they don't feel hurt when they find out by word of mouth. Otherwise, though, no one else can know.
7) No one, that is, but your new best friend, that kid who doesn't seem like she can keep a secret for her life. It's always better to have things spread by rumor rather than by yourself so you don't look like you're bragging.
8) Once word gets out, everyone will want to come over just so they can meet your Dad. But you can't just let them. Then you'll look desperate. No, you must pull the classic I-just-want-friends-who-love-me-for-who-I-am-not-for-who-my-father-is spiel. Now the popular people must work to gain your friendship, which will not only make you feel powerful but also give them the opportunity to get to know you so they don't just use you and then abandon you. They'll see you're actually a nice person and a good friend, not just some guy's daughter.
9) Once the popular crowd starts hanging out with you and you can tell that they actually like you now, introduce them to your fabulous father and let them brag about the awesomeness of meeting him. Keep it exclusive. You're old friends and your popular friends can meet your Dad, but no one else. Otherwise, it's nothing special.
10) Taste the awesomeness of popularity. And then introduce me to your celebrity father as a way of saying, "thanks."
NOTE: The more I think about it, the more I realize most male celebrities are out of their mind insane. Granted, there are crazier females (**cough cough britneyspearsparishiltonkategosselinladygagaandsoonandsoforth cough cough**) but there are some more sane women. If you'd feel more comfortable going for a female celebrity, which are probably more motherly regardless, then go for it. They work just as well if not better. But I don't feel like changing this post title to "Mommy's Girl" or "Mommy's/Daddy's Girl/Boy." Although that last one really captures the real idea of the post. But Basil would kill me because there's no way she could rhyme with that.
So... yeah. The end :)