Aristophanes wrote:
1. realize she initiated, she's into you already so 2. show up and 3. buy her coffee. 4. Notice something about her you admire (clothes she wears, unique smile, etc) and compliment her on it. 5. Look her in the eyes when you're speaking. 6. Score, you've just mastered the art of a first coffee date because literally all it takes is showing up and paying attention.
Thanks for the advice. I forgot number 4, and I did offer to buy her coffee, but she said she's proud of the money she's earned, and wanted to buy her own coffee, so I figured I would just let her go ahead. At least I offered. Numbers 1, 2, and 6 are reassuring, but I think looking her in the eyes was the best tip. I did that, and it worked. She's interested in doing something together, again. I think that's a good sign. It actually wasn't as difficult as I thought it would be. I was expecting to feel really nervous, but I didn't, at all. We just conversed, and it felt really comfortable, and natural.