Well done
what you wanna do then is seclude, bring her to a place where it's just you and her.
justify your reasons + LEAD her, take her hand and GO.
If it's noisy etc, get the mood to be 'sweet'. If she's already been kinoed etc.
Hey i wanna ask you something..
what?
aahh don't worry.
No tell me!
.. I kinda like you. (smile)
She'll smile and say the same.
In that moment, go for it. She won't reject.
Then from then options:
a. Hey let's find a more comfortable spot. (venture to more secluded area to makeout)
b. let's go have some fun. (rejoin crowd)