How do i get rid of the nerves while trying to talk to the girl i like in my class?

This is college btw. anyway her name is Brielle and this girl has all the qualities I've ever wanted in a girl she's beautiful, she's funny, she's sweet, she's intelligent, and to top it all off she's a christian just like me. Sometimes I notice she looks at my phone every time on my Instagram page if that means anything and she's also really cool as well. we've joked around with each other every once in a while but I've never had a full blown out conversation with her. what should I say?, what should I do please help! every answer will help if its helpful and mature

thanks

BB13