I LOVE A GIRL, BUT I GET VERY NERVOUS WHENEVER I SEE HER, PLEASE HELP ME TO PROPOSE HER!?

I was going to school suddenly I recognized that I had left my important file at home, so I was searching a telephone booth to say my brother that to bring that file to me, I saw a telephone booth, when I went near, I saw an extremly beautiful girl there, and I fell in love with her, yes, that was love at first site. Now I want to propose that girl, and tell her that how much I love her, But whenever I see her I become extremly nervous. I am smart, good lucking, but still I become nervous when I see her. PLEASE HELP ME AND SUGGEST ME WAYS TO PROPOSE HER!