'You're like a brother to me'

[Zhukov]

Face to face. Email will sound contrived and like you spent hours thinking up what to say, because you will, and you will be able to see how she honestly feels, rather than have her reply via email. Also, it will be really weird when you next see each other in person, whichever way it goes.

Do it face to face, don't plan too much, and try to smile; you are coming a step closer to being with this girl that you really, really like. You might get a kiss.

Whatever happens I'm sure she will appreciate it.

Good luck.