Which of the following sentences is acceptable? Which is better?
(1) Each of the customers can get a cute candle for free tomorrow.
(2) Every custmer can get a free cute candle tomorrow.
(3) Each customer can get a cute candle for free tomorrow.
In this case use (3).
Native but not a teacher
Both #2 and #3 sound fine for me, though I would prefer 'every' to 'each' in #3.
To me, 'every' is closer in nuance to 'all', and thus sounds more generous here. I'd also omit 'can' and just write 'gets' - it's more direct.