Well, I'll usually go up to them and try to get a conversation going (or sometimes they will approach me), and eventually I'll ask them if they'd like to get a drink with me some time (or if we've just met at a party or other social setting, if they'd like to blow this joint and go somewhere quieter). If you want to know what I do once we're hanging out together one on one, though, I try to express interest in their lives and maintain positive body language (I will keep my body positioned toward them). I will ask them lots of questions, smile, laugh at their jokes, and make lots of eye contact. If they seem receptive I will slowly ramp up the touching over the course of the night with light touches of their shoulders, arms, and knees, as well as sitting close together, and little things like that, until things eventually develop into kissing or whatever the other person is comfortable with.