First of all don't behave like a madman or sniveler, take a shower, hold a door in front of her and chew with your mouth shut, that will provide you 80 % of success. The other 20 % depend on small things, here they are:

Don't be hasty or impudent
Keep the party clean, keep your hands to yourself, don't speak about sex and don't pronounce THE WORDS that are too early to pronounce.
Don't be dirty or scruffy. (Offensive breath can become the main problem.)
As well as absence of good breeding
Narcissism: don't interrupt her, don't speak only about yourself, your successes, failures, and problems.
Don't speak about your ex-wife or girlfriend.  Why do men do it? Can't still forgive them and forget?
Don't behave rudely
Don't drink too much
Don't humiliate other people
Don't flirt with other women
Don't produce the impression of the desperate man (it seems rather questionably if you speak about strong and deep feelings on the second day of the meeting).
Don't speak about financial difficulties or impossible richness.
Don't speak badly about women in general.
Don't thrust your tongue into her mouth during the first kiss.
 Don't start your communication with the idea that you are not ready for serious relationships
Better to put on the underwear
Better not to gnaw your fingernails
Better not to overuse you perfume
If you promise to call her tomorrow, you should call tomorrow
Try not to show your negative attitude to life (even if it is your conception)
Analyse your behavior, during the previous appointments, mark your mistakes, think them over and try to avoid them in future.

In order to help you as much as possible, we will tell you how women imagine the ideal behavior of a man at first meeting. What do they expect from him?
1) He looks at her, shows his interest to her problems and life, asks questions and listens to her answers carefully
2) He behaves himself as a real gentleman. Opens the door when they enter the restaurant. When he pays for the bill he shouldn't even look at the lady.
3)  He presents her flowers and champagne. And invites her to the restaurant, not to the bar, to drink a couple of beers.
4) He has a good sense of humor. That doesn't mean that he should behave himself as a famous comic. But if you both laugh it can help you to become closer.
5) He is kind and attentive. In this case woman can expect the same attitude in intimate sphere.
6) He is passionate and can kiss well (the kisses should be soft and warm and can take her breath away)
7) He is fair and sincere
8) He is intelligent, respects a woman, is self-assured. It's a man that always knows what to do, that's why better to think over the plan of your meeting in advance.
9) He is sensible, but not a ditherer.

And one more thing: Be natural, you have many of the traits of character, given above, so why do you take a back seat?