How do i make this girl my girlfriend?

[Bass]

OK, i'm going to introduce myself. My name is Bassel i'm 15 years old and i think i'm in love. Since he beginning of the year I've been wanting to speak to this girl and get to know her because she seemed nice and i had this weird attraction to her. Recently she started a conversation with me because she noticed that i was in all her classes, but that was one of the only times I've ever spoken to her. I was wondering if chatting her on Facebook was a good idea, and after i get to know her and i feel comfortable starting conversations with her, how do i make her my girlfriend? Thank you for reading, any help would be greatly appreciated keep up the good work.