Just moved in to college and I’m getting to the point where I can pretty much approach anyone (albeit with decidedly over the top openers sometimes); and several times girls have “opened” me. But I can’t really seem to conduct a conversation that leads to numbers close etc. I can’t “hook them” as Neil Strauss wrote. Some advice on this?

Edit-- Have not really gotten to ask for a number yet. The conversation doesn't really last long enough. I don't feel there's enough real rapport to go forward without it being kind of awkward; however, with one girl I was really about to; and it does occur to me while I'm writing this, that I could get their number, ask them out to somewhere where it's more private, and then proceed with more conversation, physical touch/escalation, etc.