Kiss her neck.this will make her horny more or less if this doesn't jump out of your window or moving car depending where your doing this. After kissing her neck move your hand and un do her bra its easy when you master it :L. If she pushes you away kill your self. when your in go with flow
You squeeze it, but gently. In that way you get pleasured, but in the same moment she don't get hurt.
Then you can move forward to something more kinky, but slowly. Listen to her breath to see if she enjoys it or not.
When I did I got 465 hours community service (duing me being underaged, and in Norway they can't inprison underaged people), but I hope it goes better for you