Went to get a sandwich yesterday and this gorgeous girl served me. She was being subtly flirty with me while taking my order, I instantly picked up on the IOIs so I went over to have a quick chat/ask her about herself while she was preparing my food. (she was generous with the fillings too which was nice)
The whole encounter was only 2 minutes from start to finish but I knew it was now or never so while she was handing over my food I just shot my shot and asked for her number.
She blushed and said "sure" then wrote her number down on a blank order ticket and handed it to me, she asked for my name, told me hers and that was it.

I'm pretty new to this, so the whole encounter just took me by surprise.
Its the next day and I don't know what I should text her.

Some background for context: I'm a mid-20s fairly attractive guy (or so i'm told) but I have barely any game, if any at all. I've always been in long term relationships/worked a lot so never really put myself out there till recently.