At the end of your shift, ask her to go do something "fun".
Not fancy dinner or anything like that just yet, just see if she wants to go to a movie or meet at a burger joint on your break / when you get off.
At the bare minimum, ask to be with her alone somewhere. Since you have a little bit of confidence issue, this will help you go do something that isn't totally "weird" or uncomfortable.
Tip though - Ask her to do it within 24 hours. Don't ask her to go do something next week, but do something after work or "tomorrow".
This shows how spontaneous you are, but not over the top. Remember - This isn't a date.....yet. So just chill and let things take their course.
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