cherrybim – You do that and let me tell you, you will have a lot of girls going OTD. I know, I for one would go OTD in the tznius sense in a minute if some random people think they can tell me what to wear.
Speeches for the most part don’t work because:
a)they speak way to much about it so no one listens after a while.
b)people feels like oh that’s just a chumrah and I hold differently.
c)everyone makes sensitivities assur. Be clear when its Halacha and when its not. A red shirt can be permissible on one person, and be totally tznuisdik.
It’s also hard to find skirts long enough. Many frum stores do NOT sell tznius clothing but since it’s from (insert Jewish store) it’s ok.
There’s a problem out there, but I don’t think pressuring people is the answer or speeches either.