How do you ask a girl to do it?

I need a little bit more information.

Are you dating this chick? In a serious relationship? Or just trying to find someone to do it with?

If you are, and I hope you are, in a seriously relationship - then you should talk to your significant other about it. It may be hard to ask, but talking about things like this helps.

not really dating, she's been following me for a few month now, and I kinda just accepted her. (My parents don't want me to date or anything though, I didn't tell my parents anything about her, but I like her)

maybe i've watched too much porn, but i really wanna try to do it with her... but i can't imagine myself doing it with her, let alone find a place to do it...