Apologies on the criticism of your authority.
And now I understand - the “Putz!” smiley is never ever appopriate as a… smiley, but only as an insult, and as such, has no place outside the Pit.
I’m going to go waaaaay out on a limb and disagree with some of the advice here on the assumption that the OP is pretty young. OP, if you’re… hell, 18? Then go ahead and proceed as advised: tell her you’re a lesbian. But I was 18 when my first friend came out to me, and immediately assumed he had a crush on me. Right or wrong, that was my basic asssumption (I still don’t know whether he did or not). When another friend came out to me when I was 24, I also assumed that, but he was really cool - we talked for about an hour and I finally got it through my thick skull. It turns out that gay men are almost as picky about their guys’ looks as straight women. Anyway, my point is that you should be careful just spilling the beans when you can’t honestly reassure her – if she turns out to be straight – that you don’t have a crush on her.
You might try getting the subject rolling by responding to a “He’s pretty hot” comment with something like “I wonder if any of his friends/teammates think so, too?” Point out that there simply have to be gay guys at your school or office, and that means there are definitely some lesbians around, too. If you get a neutral or positive reaction, proceed apace; if she freaks out, then you might want to dial it back… or just burst into tears, if the two of you are somewhere private.