When I write about opening "sets," what I mean is talking to people. I say, "talk to everyone" a lot, but people rarely know what I mean. I literally mean "talk to everyone."
You're not going to get better at this if you don't like talking to people. When I go out with guys, they are so intent at talking to girls that they totally forget about their social game. What sets us apart from every other AFC trying to hit on girls is that we're talking to everyone: the life of the party. We're talking to the doorman going into the club, and flirting with the bartender. We're asking the guy in the bathroom how his night is going and leaving him a tip. We're talking to the person next to us at the bar ("Hey. Is this bartender taking forever?"). We talk to the group of old ladies, and the hotties who just walked in. This is game.
Here's an example. At a concert the other night, I was talking to this guy. He seemed like just a normal guy, trying to enjoy the show. He was eyeballing every girl that passed. Eventually, a cute blonde chick comes up to me and asks me for a cigarette. Now I never let that go. I give her shit. I'm ALWAYS giving girls shit (it's part of the persona. 1 - it shows you're cool to be around, 2 - you can't give a fuck. You're talking to so many girls, you mine as well make it fun). This girl's digging it. She starts qualifying herself HARD. At one point her friend comes over, but I ISO the chick and eventually her friend leaves. I was a little tipsy and nothing came out of it. After she leaves, I tell the guy to my left, "Well, that's about all I had in me tonight." He goes, "HOW DID YOU DO THAT?!"
It's no secret. Talk to everyone. Be the life of the party. Let your confidence show and be prepared for when girls open you. I am still learning how to handle girls opening me. It's relatively new to me, but I'm pretty sure I'll get there.
Keep at it, playas.