I like this girl, how can i talk to her?

Hey, I'm a junior guy. There's this year younger girl in my 4th period band class. Now, the thing is I play clarinet which is pretty far from her. She plays flute.

She's a sophomore. I don't know the first thing about her, besides her smile is heartwarming and she's a nice person. I've caught her staring at me a few months back for a few weeks, but not anymore. Just two days ago, I saw her with a cap on. The next day, she wasn't wearing it and I said, hey where's that cute cap of yours. She quickly pulled it out and said this? and then i said yeah and she laughed and kinda smiled and then she said you wanna try it on?

and i did and then talked for a few seconds, gave her back the cap, and went back to play. now im just wondering, good signs, bad signs? like, im completely lost. ive been out of this game for SO long. how would i go about talking with her without coming off as creepy/annoying?