I would recommend ordering a S (Waist 28-30). I fear a M (Waist 32-34) would be to big. Have a great day.
I am a 29.5-30" waist and I actually prefer the medium; I was afraid they'd be loose in the waist but they're elastic and fit fine, and the cup of the small size is too tight. I would definitely recommend Medium for 30-32" waist