This is partially something that is teachable, and some of it's going to come from within you. The thing of it is that you can't be too aggressive at first. The worst thing you can do is run in for a kiss, bump your teeth, and then stick your tongue down their throat. It's not going to work. You need to be as gentle and as soft as possible in the beginning. Let it kind of escalate on its own.
If you're with a girl and you think that she's interested, go in for something very minimal and soft and see what you get in return. The last thing you want to do is immediately go right in for it. The tongue should stay out of the equation for at least the first two minutes of a kiss. You need to stay away from too much ear action and things like that. Some people... [laughs]
You're not a dog. Don't lick their face. Don't lick their ears. Keep it lip to lip for a while and see where it goes. If she starts going for something else, maybe have a shot. If it's your first kiss, seriously keep the teeth out of it. This one's really tough. Keep it simple. Keep it soft, and keep it gentle.