thers this beautiful girl that i work with, and iv struck up conversation with her and been able to neg her successfully, but now i dont know where to go with it other than small talk. what would a PUA do?

Negs are just to disqualify yourself. Assuming you build attraction (DHV story telling is an example), You followed it up building rapport through qualification and comfort.

Could be like.

You: So, what do you do for fun?
Her: I watch movies.
You: That's cool (communicated in a way like your IODing her since that's a really general answer)
You: What else? A lot of us watch movies for fun.
Her: I love to go surfing.
You: Omg! Surfing is so much fun! (You can act interested here, and if you surf yourself, you can go into stories, or have her tell you stories about her surfing, etc...)

Point is, you wanna start screening. Guys with like tons of women in there lives naturally do that. You can be real about it, or fake it. Also, if you fake it, don't act interested in every thing she says. Otherwise it will be just weird.

Also, don't follow it up with one question after another with rapid fire. Small talk, throw in some random BS. The deeper stuff she can reveal about her self, the better. Vice versa if she ask you.

If I am coming across as being super cool. I love going into subject about me being in middle school since I was a complete dork.