After struggling throughout most of my young dating life (I didn't get my first kiss till I was 24), I read a shitload of books on attraction, psychology, and success - so much so, that I wrote my own book on attraction.
And here's what I can come up with today:
Confidence - A woman is attracted a man who has shoulders to cry on, not a man who needs to cry on a woman. Woman want to be rescued by a knight; most are not conditioned to be the rescuer.
Provider - Since the Stone Age, women have had to stay in to care for children while men went out hunting for saber tooth tigers. Things haven't changed much. Women are attracted to men who can provide such as food, safety, companionship, or the fulfillment of a dream.
Good genes - We are pre-conditioned to seek the healthiest people so that we mate, procreate, and pass on those healthy traits to our own children. Women are attracted to those who look "alive", men who are go getters, not bitches and complainers.
Laughter - We like people who make us feel good. When a woman is constantly laughing and having fun around an attractive (or even sorta attractive) male, she will want that feeling often, which means that she will to be with him often.
Attention - Women want to be noticed. They want compliments so that they could feel good about themselves. They are attracted to men who make them think highly of themselves and men who breed self-confidence in them - confidence that almost any man with decent social skills could provide.
Conclusion: If you don't smell bad and are confident, rich, handsome, funny, and attentive, you will attract women.