Mystery's M3 Model

Have her EARN your interest
Be interested in something besides her looks
A simple example of this is Mystery's Bait-Hook-Reel-Release method:

Me: "Hey... tell me.. are you Swedish?" (Bait)
Her: "Yes... why?" (Hook)
Me: "Oh my god... I'm a SUCKER for Swedish girls..." (Reel)
Me: "I can't even talk to you anymore..." (Release)
This is called qualification, when you qualify the girl as being worthy of interest. The B-H-R-R method is just ONE example of qualification, where you can deem her cool/worthy/interesting based off on pretty arbitrary bullshit (you may think it's arbitrary but the girls will be intrigued). You can also make them work harder to earn your interest, through statements like:

"Hey, at first you seemed kinda dull... but now that I've talked to you a bit more, you're pretty fun."
"So... what do you have going for you besides your looks?" "Blahblahblah" "Cool, I like that."
"I like your energy."
"I like the way you carry yourself."
[edit] Comfort
Before you can transition into comfort, it's a pretty good idea to isolate, if only a bit. Like, lead her outside or to the other end of the bar or if you're all sitting in a couch, reposition so the two of you are talking to yourselves at one corner of the couch. Just get some alone time.

C1 - Conversation

C1 is usually an extension of A3, except you're no longer just trying to qualify her. You guys should be just CHILLING OUT and TALKING. This is to create a sense of COMFORT with one another. You know how old lovers can just relax together and just shoot the shit, sharing intimacies about themselves without really worrying? This is the ultimate goal of COMFORT and C1 is the beginning of that. So relax, tone down the c/f, drop the negs.... it's time to see if there are any commonalities between you and her (there almost always are... and if there aren't and you still wanna fuck her, then it's not that hard to make them up).

By commonalities I mean... even if you are an Econ professor and she is a Penthouse Pet, there are still commonalities you can build by discussing OUTLOOKS and PERSPECTIVES on things (rather than the actual subjects themselves). Emotions and ideals and such can always be related to on some level.

Also, C1 is usually the last phase that you deal with at the meeting location (club, party, whatever). However, it is important that you end on C1, rather than A3 or even A2 (when she is attracted), because it is NOT ENOUGH to insure a second meetup if all you do is attract. You MUST qualify and you MUST establish some comfort, so she doesn't just dismiss you as just another party/club-guy.

C2 - Connection

Connection is just conversation taken to the next level along the commonalities and "our-world" train of thought. Not much to add here except keep talking, keep sharing, keep creating that "us" vibe. Things such as vulnerability stories and letting her see a different side to you (maybe a more tender or chill/laid-back side) is good stuff. Kissing should take place at this stage.

This stage can take place over several dates.

C3 - Intimacy

C3 may or may not be in the same location as C2. Basically, C3 kicks in when you are in a prime position to FULLY CLOSE THE DEAL. So maybe you guys have a date at your apartment, cook dinner, cuddle together, talk a bit, kiss a few times (C2)...

Then the kissing becomes more intense. You guys are alone, so it's good to go. The kissing turns into heavy making out/etc. Bam. C3. You're ready to close this shit.

Seduction

This is it. And this is a CRUCIAL step. You MUST seduce (fuck) her if you want a serious sexual relationship. Set the tone early.

Obviously, if you are in HS or dealing with a super inexperienced girl, you can slow down and adapt accordingly (to a 13yo virgin, making out may mean the same thing as sex to a 25yo partygirl in terms of courtship).