Compliment something genuine about her.
“Congrats on the first place win in the 5K, that’s awesome.”
“Hey, you knew that song that was just on? Wow, I thought I was the only one, haha. You have great taste.”
Choose something you can tell she’s put effort into.
“Your notebook is awesome. Did you decorate the front yourself?”
“You’re on the diving team, right? Congrats on making it to the finals. That’s amazing.”
If you compliment her appearance, go with something unconventional.
“That shirt is awesome, it looks like you cut up the bottom yourself. Or did it come that way?”
“Did you do all the drawings on your shoes? They’re really cool.”
Follow up your compliment with a genuine question.
“How long did you guys have to practice to get that song down? It sounded really good.”
“Where did you learn to play soccer so well?”