Here's a big one: Lead. Being the guy, you want to be authoritative and decisive. Girls don't like to make the decisions, so if you've just had coffee, don't ask "So what do you wanna do now?". Yes, it may work with some girls, but generally girls want their man to be a man who knows what he wants.
Here's something that's also incredibly useful but often overlooked.
Be genuinely interested in what they have to say. A lot of the time people forget to ask questions and show an interest, rather they keep talking about themselves whenever they get the chance.
No girl has ever complained that they talked too much on their date. Ask questions!
It's easy to be in a conversation just partially listening to what they're saying, while you're thinking, "Ok, what am I gonna say after this.. Once I've replied, what will the next conversation topic be?". By doing this you miss a lot of the cues which lead off onto other questions naturally.
Here's an example of a bad conversation:
A: What kinda things do you like doing in your spare time?
B: I'm pretty interested in cooking, I recently started taking cooking classes.
A: Oh cool, I'm not that good at cooking, but I know enough to get by.
B: (---) Maybe you should take lessons too.
A: Haha, maybe I'll join your class.
*Tumbleweed*A:
What else are you interested in?Here's an example of a better conversation:
A: What kinda things do you like doing in your spare time?
B: I'm pretty interested in cooking, I recently started taking cooking classes.
A: Oh cool, I'm no good but I'd love to learn. What's it like; are you enjoying it?
B: It's been really fun so far, I've learnt lots of useful techniques and some pretty tasty recipes.
A: Awesome, what's your favourite dish that you've learnt so far?
B: I really like the Parmesan-roasted chicken with sauteed potatoes and asparagus, it's delicious!
A: Are you confident enough to make it for someone else to try?
B: I've practiced it a few times so I wouldn't mind
A: How'd you like to cook for us tonight? I'll bring a bottle of wine..
(You get the picture by now, surely...)