I am in 8th grade, and have recently found out that I am bi because of a friend that I have a crush on. She has said that she liked girls in the past. I know this is the real thing because I have had crushes before but I just can't get her out of my mind. I want to confess to her but don't know how. We joke about being bi a lot so how can I confess to her without:

1) Sounding cheesy

2) Not scare her off

Please help me I love her with all my heart and need to tell her.