What do I go to get this girl to like me?

I'm 13 and so is this girl... I REALLY like her, for a while now, I told her the other day (I knew she knew I liked her but I had to tell her myself) and we talked and I asked her out and she denied me but, she being my best friend, was at least polite...... I NEED TO DATE HER!!!!!!! Shes super special to me... If you can think of any songs I can sing and/or advice to make her like me like I like her, that would help a lott................ Thanxx