Hello PUA Forums,
I've been working on this one since December 2011. I'm defining social dance as swing, salsa, bachata, blues and other partner dances. There are just a couple of steps that change a social dance into a great opportunity for pick-up. When I first started, it was easy to ask a girl to dance with some basic skill, but I was really struggling to build attraction beyond dancing one song per girl.
1) choose your target (don't get distracted)
These are very target rich environments. Generally gals are more interested than guys in learning how to dance. It's easy to get distracted dancing with whoever is standing nearby.
2) ask the same girl to dance multiple times (but not in a row)
With the exception of tango, you only dance one song in a row with a partner, unless you are working on a new move. This give you the opportunity to re-approach throughout the night and gradually build interest.
Now that I'm taking classes I have the excuse of practicing the new moves for two songs in a row, but still it's better form to ask the girl to dance later that night. Sometimes I'll even tell the gal that I want to dance again later that night. I've asked gals to dance right before the end of the song, and I'll still respect the custom and thank her for the dance after only dancing for 30 seconds.
3) find out who she's there with
My wing Ray pointed out the corner where my target's friends were hanging out while she was out dancing. I went in and started talking with them giving me lots of social proof when she came back from the dance floor to rejoin her friends.
4) alternate between dancing and chatting
The biggest mistake that I made with social dance game was focusing on making engaging conversation while dancing. Unless you're really in touch with the music, it's better to focus on your dance moves while you are on the dance floor. You can easily move back and forth between chatting off the dance floor and dancing on the dance floor. Building attraction (kino of dancing) and comfort (conversation).
A couple of other notes:
Don't follow the gal around the dance. Give her space to socialize and take the opportunity to chat with other guys and gals.
Show confidences. Even if this is your first time, you can dhv by showing that you have the confidence to try new things.
Many dance studios offer beginner's classes before the social dances. This is a great way to find the style of dance that works for you.
Since December, I've been going to dance socials at least once a week and taking at least one dance class a month. Let me know if you have questions. I'm happy to help. I'm a big fan of dancing in general, so being able to practice PUA is just an added bonus.