Thirteen year old biual girl- how can I "come out"?

Give it a little more time Maddie. There is no rush here. If you were my daughter, I would love you unconditionally, I know your parents will still love you the same, it might be a little awkward at first like anything of this nature. What you are feeling is ok, there is nothing wrong with it, my daughter is only eight, but there are clues as to the way she might be later on, I am not worried either way, and it might seem strange, but I think a parent, if they are openminded just knows. Maybe that's why I spend so much time here, in this section. Like I said before, at 13 to 14, there is no rush. Just enjoy life as it comes. Come out a little later if you can. Maybe I am wrong for saying this.