Here are a couple of articles that should get the thought process going well. This is not a full endorsement of everything said. But, it will stimulate thought.
"Modesty isn't something that's easy or popular. Neither is it a list of do's and don'ts or clear-cut rules. Modesty starts in the heart and the outward appearance is what reflects what's inside. Nor does modesty simply apply to clothes; true modesty is evident in the way you carry and conduct yourself.
So, why do we dress modestly? We dress modestly to bring glory to our Heavenly Father and to honor Him with what we wear. We dress modestly to protect our brothers and brothers-in-Christ, so that they may at least be spared the visual assaults when with us. We dress modestly to honor our future husbands, saving ourselves for them alone. We dress modestly for the world, to show them that yes, there is something different about us as Christians."
Taken from a blog I find very helpful on modesty- Maidens of Worth
*if you scroll down, on the left, they have a list of categories and you can click on Modesty and Feminimity. Hopefully you will find this helpful, sir.
Here's a good one from Stacy McDonald's blog. She has 6 other posts under the "modesty" tag in the sidebar, too, but this one is "seasonally" relevant. The Empress Has No Clothes