If you're the nervous one then you could just let her make the first move… There are a lot of YouTube videos for this question, but really you can't go wrong. Like in this movie called "a walk to remember" there was a dialoge that went like this:
Boy says "I think I'm gonna kiss you"
Girl says "I might be bad at it"
Boy says "that's not possible"
Awww so sweet, I love that movie
Anyways, I feel like kissing, at least first kisses, should be saved for special moments like when you're both happy and on a date and enjoying eachother's company. Then just go with the flow, Good luck!
