How do you make your girlfriend want you to kiss her?

You can never make someone want to do something they are not comfortable with. Your best bet is take her some where nice, treat her well, put no pressure on, maybe just a walk or the movies or a cafe. Talk, that's always important, but listen as well. Always try to make her feel comfortable, at the end of the date , when its time to say goodnight etc, lean forward for a kiss. Do not go in full on, try to be gentle and sincere about it, if she moves back just say sorry and some thing like "I really wanted to kiss you, but I can wait till you are ready."

Trust me even adults suffer from the same problem when first dating, it doesn't get any easier with age, its always nerve racking. Also once you have kissed don't expect her to want to kiss you all the time. There is a time and a place for it all, and is always where she feels more comfortable, never push the issue.