Take the attention away- Anytime you start talking to women, redirect the attention to her friends, or your friends or even other women! The minute you take away some of your interest, is the minute she will work hard to get it back. Women do not want a man who is giving 100% attention to her, believe it or not; because it means you were easy to get.
Give few details- Scarcity is key here, never give out all the information about yourself, and especially what you want- never tell her. When you don't just hand out details about your life, and your feelings she will work hard to get the details then. Most women encounter men who come along and just tell her everything right off the bat, and she reads him like a book and moves on fast then because he is too predictable. Less details keeps things interesting.
Surprise her- get her interest up by telling her that you noticed something weird about her; but do not tell her what that thing is. She will be curious to know what exactly it is that you were going to say, but didn't- since she is so used to easily getting information and questions answered, the minute you don't she will be wildly chasing you to get that answer.