You know how nature (and science) reminds us to not think in absolutes? Yeah, every first date you have will be different. So I'm going to say my piece, and it'll come across as trying to teach English (Do this when this happens, but there are exceptions, like this because of this rule. There's also this sole exception amongst exceptions just because.)
Be yourself. You are who you are. You may not tell every single female you meet that you play D&D and keep a small child locked in your basement, but the thing is, you do. Don't shy away from that if it arises and end up projecting a different image of yourself. Those who mind don't matter, while those that matter don't mind.
Watch not just what you say, but how you speak. You know, the sarcastic/exaggerated language you use around mates. While they may get you and understand what you're actually saying, she's going to have no idea. You've got to get to know one another first before you revert to "SneeR speak".
Don't assume too much. This is mostly in relation to "the male pays for everything". Don't get me wrong, chivalry and male pride are there in abundance in my personality; however, not everyone feels the same. I have received dirty looks and barbed comments from females who believe that I'm offering help because I think they cannot pay for dinner, or lift the speaker or open the door for themselves. I'm all for you doing it, hell, I do it myself. So offer, but be open to the (slim) idea that she would rather pay for herself. I mean, who doesn't like a free dinner?
A good way to converse is to actively listen. Not just sit there, stare, and blank out. Ask a question, then further that discussion by picking something from her answer and ask a question about that or relate it to a story of your own. Watch for using the latter too much. You don't want to be talking about yourself the whole night. On the same token, you do want to talk about yourself a bit so she gets to know who you are.
Honestly though, things like don't touch, no kiss, be humble, be confident, be aloof, be attentive... well it all depends on you. If you feel too uncomfortable because you're acting unlike yourself, it'll show.
If I seem a little verbose, it's because I want to illustrate my points. I've found that it can help (at least it has for me).
Good luck!