Go sexual. By that I mean start making sexual references in what you are talking about it. Don't overdo it because you'll sound like a little 7th grader in puberty or something. When you make them it can be to her directly, a whisper, or even in front of the group.
YOu'll catch me staying stuff like, "IF you keep eyeing me like that, I'll pin you against the wall, and make a woman out of you in front of all these people." IF she doesn't say anything negative to this, or is just quiet then mentally she has accepted this. Meaning you are cleared for takeoff.
You need some comfort to get the close that's to be sure. The more comfort you have the less LMR there is. If you have some basic rapport you can take the conversation sexual, amp up the kino escalation (touching, makeout kissing, sexual touching, etc.).
Then you will need push/pull tactics to get the heat up. For example be making out with her, then show a little disinterest, then go back to it, then stop again, etc. This gets girls wanting it really bad. It's cruel I know, but then again so is not getting laid.
Then you just have to pull her somewhere to have sex. When you get there it's ON!!! Just be prepared to handle Last Minute Resistence and enjoy.
Check this out, it'll give you some more ideas, and tips.
http://jsmooth26.blogspot.com/2009/02/s ... t-lay.html