Well I watched this show where they were scientifically studying what attracts people to each other.
Warning: These are broad generalizations.
What scientist have found that attracts women to men. Basically it boils down to "Do you have features that would make for having lots of happy, healthy, children." Even if the woman doesn't want children, we're ALL still programed to look for these features, men and women.
So, what makes for lots of happy healthy children?
First of all genetic and bodily health. Symmetry is the foremost sign of genetic health. If you're not symmetrical, there's a good chance your genes are messed up somewhere and there's a greater chance your offspring will be born with something nasty or be unsymmetrical themselves. If one eye or ear isn't the same shape as the other, you're gonna have a harder time finding a date. Then, of coarse, there's your over all health. Rippling muscles. Can jog for days without breaking a sweat kinda thing.
Smell also plays a roll. Bad smell means you don't take care of yourself, how are you expected to take care of someone else? Deeper than that, women get subconscious hints of how healthy your immune system is from your smell. Parents with healthy immune systems = children with healthy immune systems. If you're going on a date, wear cologne. NOT TOO MUCH COLOGNE. If people can smell you before they see you you've failed. Just go home. Smell is to be subtle, not over bearing.
Community status. We are communal creatures by nature. Someone high in communal rankings would bestow advantages onto their children. Thus guys with lots of friends, or guys that are famous, are attractive prospects.
Material wealth. If a guy can afford a tricked out Lamborghini or to wear a 5000 dollar suit, he can probably afford to support the needs of the screaming human larva we call "babies". They can also support the woman herself, so for the selfish shallow types this is a big deal.
Comfort level. This is a big one. If a woman can't feel comfortable with you, she isn't going to want to bear your children and isn't going to want you raising them to be like you. What's comfortable for women? That's entirely subjective and personal. Generally, having an easy attitude, sense of humor, etc are attractive. But then there are women who want pricks, there are even women who expect to be ignored or abused and find comfort in that. These women generally came from broken families with abusive fathers. Women often look for guys who remind them of their fathers because they are comfortable with their fathers. Even if those fathers were pricks. So, if a girl says "You remind me of my dad" that is a VERY good thing.
Above all, work on your social skills. If you are creepy, acting sex starved, acting DESPERATE etc etc you are not going to get date. I was at an anime club one day and in comes a group of girls. One of the guys I was talking turned, pointed, and shouted "Look! Girls!" I face palmed and said to him "You are going to die a virgin..."
Again. These were all broad generalizations. Please don't send the angry mob at me if your personal experiences have been different.