Firstly, it was day-game so there is no rush, although don't let anyone get ahead of you if she is something special!
When you feel the time is right, morning, afternoon, evening text her with something like;
''Hey, I was watching a movie with my buddies and the girl in it just reminded me of you!, too bad it was a horror, lol''
That shouldn't offend her, but it will get a response where you can drop the line in, DO NOT DIRECTLY ASK! Something that is fun and responsive, with a DHV and neg usual does the trick!
''[Random text], remember about .......... on ........., this is open ended so if she doesn't respond to your liking say it was only a role play. This will be on her mind and you can ask her again at a latter stage.