How to persuade my classmate to have sex ?

I am 23 year old and i am in love with my classmate, she is kinda of nice and really good. We both like each other. But i am not finding a chance to persuade or ask her to have sex with me. She has a nice curvy model figure with a dark tan skin but i am not getting this thing to ask her out. We sit in same class, eat together in canteen and go around out side college most of times. We both confessed love to each other few months ago. But i have never had intention to have sex with her. Recently we watched a movie during a intimate scene she held my arm and rested on me.I feel she too needs some intimate relationship with love and it is time to move on to another level called sex. When would it be best time to approach her for sex or how to persuade her for sex ??