Come up and casually ask her how her day is going. She's give you a standard canned response like, "Good". You then take that and run with it.. "Good? Why not great? Rate your day for me on a scale of 1 to 683." She'll giggle. Then ask, "Can you remember the last time you had a 683 day?! What does it take?" And improvise from there. Finally tell her she's cute and that you're curious about her. Tell her you want to grab a coffee and number close. If she's working the checkout line, you won't have much time for a long conversation because there will be other customers. You might want to split the conversation up between multiple visits. It will look natural cause you're a regular at this gas station.
Good luck!
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