I've had this happen to me like 4 or 5 times past month. I want to set up a date with a girl, she agrees but she's not sure when she would be available during the day that we agree on and leaves a message "ill let you know" and in fact does not let me know.

Talked to my friend about this and he told me i need to be specific while proposing dates, so, instead of asking her to hangout friday night i should say "Meet me at x at 9 on friday" so i tried that but i still got mentioned answer today by a 9/10 which seems interested when we hangout but distant on instagram. Any thoughts on how to approach this or similar situations?

I know she did not flake on me (yet) and technically speaking we are about to hang out this friday, but how do i minimize the chance of flaking on this point?