How do I tell my best friend I like her if im a girl?

how do I tell my bestfriend I like her? like everytime she touches me or looks at me I wanna kiss her... and shes kissed a girl before I just dont know if she'd go bi for me cause I wanna date her... cause every time she gets me jelous with someone else. im just scared im gonna loose my best friend if I tell her or try anything thats the onything holding me back... and some of the people I told about her say shes flirting back ..and I did some research and some of it true but idk what to do about it even it was true.... please help!!!!!

tell her this:CAN I TELL YOU SOMETHING..DONT GET WERIED OUT BUT WHEN I FIRST MET YOU I HAD A LITTLE INNOCENT LEZ CRUSH ON U.....BUT USED TOO or somethin lik tht then just brush it off act like nothin....IF SHE LIKES U eventually she will ask u if u still like her!hope I helped:)