Assume attraction, and act like you already know her. Tease her about things she does "all the time" even if you have no idea whether she does them or not. Learning about female nature via the Red Pill helps a lot here, as all women are hardwired the same. It's just the software that changes a bit.
One thing Mystery definitely got right is the three stages of seduction; Attraction, Comfort, Seduction. By skipping Attraction and starting with Comfort, you're a "nice guy" and friendzoned. By skipping Comfort and moving straight to Seduction, you're a "creep" unless you're super hot and/or famous.
By assuming she's attracted to you and already providing comfort through familiarity, you're already moving towards seduction, during the first chance encounter.
And put your goddamn hands on her once she's clearly comfortable. I like to put my hand on her shoulder and look at her like a film producer looks at his movie star; "You're mine. Together we can slay."
End the interaction either by instadating her ("I'm thirsty, let's grab a drink...") or saying her name and "...we'll continue this conversation."
Hand her your phone and get her to put her number & name in and give her a quick ring so she'll have yours, or if you're feeling more confident, take her phone and put your number in (saving yourself as "awesome guy" for fun) and call your phone. If you're feeling super confident, hand her your business card with your name and number and don't bother getting hers. "See you..."
Edit: When saying goodbye, right before I walk away, I like to kiss a woman on the hand. It's very divisive; either she will absolutely love it and practically fall in love with you there and then, or she will not like it at all and make it obvious. She could also exhibit no strong reaction to it, but inside she liked it or didn't. Don't worry about it either way. You aren't putting her on a pedestal by kissing her hand, you're giving her a taste of the kind of passionate, high value guy you are.