A lot depends on what you're looking for Dan. If you want a genuine relationship with her then Xena and others offered great advice. Smiles, being a gentleman, all that works. I've always been attracted to polite confidence. If all you want is to bed her and spread her then use a very forward line.
Gadget if it's a friend they you need to cowboy up and ask her out. Doing lunch together is common for a first date and gives you an opportunity to talk about common interests. Now if you have already reached the friend stage a woman might find a little nervousness charming even so don't worry about it. The worst that will happen is she will politely decline and you'll survive. I have never been nasty to a guy that asked me out unless they keep asking me out over and over. Then I'll make them cry. But I have guy friends that ask me out and I can't think of a single time I've tried to hurt their feelings.
Oh and we can tell if you are trying to be someone else. That none of us find charming.