Inquire about what she's holding
At a bar? Naturally cute-girl-over-there is holding a drink, so don’t bother with a stale “Whatcha sipping on?” -- that's the NECCO Wafer of pick-up lines. But if she’s toting an object that may reflect an interest of hers (gym bag, art portfolio, etc.), then point THAT out to spark further conversation, ideally about her.
“I was reading a book on the train when the cute guy across from me asked if it was a good read,” says Bailey*, 29. “He had a book in his hands too, so even if it was just a ploy to talk to me, the common interest factor helped his cause. We ended up chatting instead of reading the whole ride and when our stop approached, I took him up on his offer for coffee.” And hey, if she’s carrying around binoculars, maybe she’s ALSO into bird watching and you’re a match made in old-people-pastime heaven.