hello,
Ok, First, lets blow this balloon and get back to reality:
You admit that you are a bit AFC'ish, never tried any technique etc, etc. You never been on a date, etc. All of a sudden, life smiles at you and hell, you decide that now is the time to at least sign up and ask questions here. Dont get me wrong, you are darn right to come here, and you are darn right to ask you questions. I dont know what your expectations are with this mystery woman, but i hope you dont believe that we instantly transform you into casanova 2000. That just aint possible.
now, breaking bad already gave you some excellent advice.
I would go after her as well, if not reachable, call her the next day. Hey, what can i say, i would be freaking curious! I like women who are strong and take initiative and who can do it in an elegant way, so i would tell her that. Then i would say that you are curious about who she is and that we should meet, for a drink, a coffee a whatever it is you would like be doing.
As for the "date" itself: Be honest. That is the main headlight. Be honest to yourself and towards her. Concretely that means: if she dressed up nice and you htink she is pretty/gorgeous/just smoking sexy, tell her! and not after 2 hours when you finally found a way of how you would tell her, no. Tell her when it comes to you mind! be honest!
Also, if you are honest to yourself, you do want to know who she is right? So ask good open ended questions about things you would want to know. Like, not only what her job is, but does she like her job or not? Why? if not, would be her dream job? why? Is there something in her life she is passionate about? something she could do all day and never get tired of it? What are her dreams, etc. You get the point. You dont want to stay on the surface, you want to get to know her!
So in short: be relaxed (you have a bit of anxiety there, that is normal). Be honest and be interested in her. If she isnt really much of a talker, make her talk. Ask the question and wait for the answer while you look expectingly in her eyes

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As overall: You should perhaps see this as your first step towards pickup. You are in luck, cause you dont have to approach this time. See it as an invitation to learn more. we are happy to help you.
well, hope i helped out a bit as well. Good luck!