How do you deal with a clingy person?

There's this girl who, for some reason, believes that we're best friends. I don't even know this person, and she's always hanging around me and trying to be all 'best friends-y'. Well in class because of a seating chart I have to sit next to said person, and when I was going to move nearer to a friend, she glared at me and said ';Don't tell me you're leaving me.'; In addition to creeping me out, it irritated me and I've tried to make it clear that we're not friends. However, she doesn't seem to realize that I don't want to be near her, and she keeps pestering me and bothering me nonstop - it's very unsettling and unnerving. How do I get her to leave me alone?How do you deal with a clingy person?
She is trying to control you with her neediness. Don't let her do it. The next time she comes up to you, just tell her your day is really busy and you have to go. Then walk away. If she follows you, turn and say, ';I told you I'm busy. Bye!!'; Keep doing that and she'll eventually give up and go after someone else. Good luck!! : {How do you deal with a clingy person?
Maybe she is insecure and maybe you were nice to her one day, so she took that as a sign that you want to be friends. Try to be nice, let her down easy, nod occasionally and rarely talk to her, soon she'll give up.
Dont text her back and ignore her when she is around. She will prob get tired of being ignored. OORRRRRRRRRRRRR you may try to actually be her friend, you may like her.
oh my goodness, this happened to me several times.

The problem with my situations was that i get real creeped out so I try to stay away from these people once the clingyness starts. The sad part is in the end, we're not even friends anymore.