You need to learn to possess the traits of an "alpha" male, or at least imitate them. Look your best, without appearing to try too hard. Always smell nice, but never overpowering. Be confident, smile, and greet people in a positive manner somewhat frequently. You need to master the art of teasing, without going too far. Teasing is often a good way to build attraction. You also need to attempt to break the "touch barrier" by casually touching their hand while talking, or some other non-threatening place.
If you're in a bar setting, you should sit one seat away from one of the people you're interested in starting a conversation with. If it's just her and another gal, casually interrupt some of their non-serious conversation with a related and interesting story or comment. You should segue that into a question about themselves. People love to talk about themselves.
As I bartender, I see people that often have either very poor game, or amazing game. You really need to practice these interactions. Once you get the feel for it, you can display your personality in the positive and interesting person you most likely are. Most of all, have fun. That's what life is about.