Either you, her, or both of you wearing them.
Personally, I think I look better with glasses - classier, not nerdy (though some glasses I tried on made me look like a total nerd).
I've never made out with a girl while wearing them, and ditto for a girl who was wearing glasses at the time.
So, for those who have gone before me - do glasses get in the way? Should they be taken off?
Thread: Kissing a girl with glasses