How should i ask her out?

Theres this girl, who i really like and she likes me alot to. I can tell since shes always showing body language, and getting closer to me. Anyways, i was gonna ask her out tomorow, but im not sure how. Keep in mind im 13. Whats are some good ways to ask her out? I was thinking to strike up a c onversation, then go im gonna be real honost with you... I really like soo do you want to go out? I am not exactly sure what to say. When class is over ( my only class with her) i was gonna strike up a quick convorsation, then do what i said ( in the other sentence.) After she says yes, what should i say? Im not just gonna stare at the sky and be like bye! Should i say, haha alright ill cya later (her name) The first best answer will get 10 points!