What does modesty really mean?
mod·es·ty /ˈmɒdəsti/ Show Spelled
1. the quality of being modest; freedom from vanity, boastfulness, etc.
2. regard for decency of behavior, speech, dress, etc.
3. simplicity; moderation. *
On the Good Christian Team, I think we go a bit far in search of modesty (#2), sometimes to the point that we look like we're wearing costume. When we go that far, it's easy to stray from modesty (#1).
This is not to say that I think that we should be cheerfully wearing what everyone else is wearing, particularly when what everyone else is wearing is either ugly or overtly sexual, if not both. However, when we're choosing our clothing, we need to be aware of the prevailing social climate. You don't wear white to a wedding, you don't wear orange to a funeral... and maybe you shouldn't wear a cape dress to the beach.
The idea behind modesty is not to make a spectacle of yourself. This is hard for me! I'm pretty eccentric, and I like vintage clothing and vintage styles. I just realized recently that vintage silhouettes are so dissimilar to modern silhouettes as to be somewhat... immodest. Yep. That high-necked, low-hemmed daydress? Well... no one else is wearing a bodice that fitted, and yes... everyone is staring.
Check out this photo collection of vintage swimwear. On the rack, in pictures it seems absurdly modest. Ridiculous. And then you see the people in them and ... oh my! You'd never see anyone this immodest at the beach nowadays... why, these people are totally comfortable with their bodies! And they're not wearing five layers of spandex to make it less obvious that they have bodies indeed.
Personally, my rule of thumb is a 10-20% deviation from the "norm" (whatever that is) won't be noticed, and will thus be perceived as modest (#2).
We can never forget that we're ambassadors to a foreign land, and we need to not freak the natives out too much!
*This definition from dictionary.reference.com