The more you get to know her the better you can talk to her. The better you understand each other the greater the chance is she wants to be with you. It just takes time.
I usually only take interest in people who message me first, but in essence just try to find a relatable topic to talk about and break through the ice so you feel more comfortable around them. That helps in developing a friendship because you feel like acting more naturally.
Make her laugh
Talk with her
Make her laugh
Don't be desperate
Lay off the lewd crap for a good long while unless she brings it up herself. Be patient as not everyone can reply every 5 minutes.