Modesty can be a difficult topic. To borrow (and modify) a phrase "modesty is in the eye of the beholder". What one person sees as modest may be over the line to another person. That's one of the reasons that fathers need to take an active role in this issue with their daughters. Just as we don't know how they think in many areas, they don't know how men think in many areas.
For example, I've found that many women are completely clueless when it comes to how men view their clothing. Often women think they're being cute or in-style when what they're doing is drawing attention to all or parts of their bodies in ways that they probably should be uncomfortable with. Women are often oblivious to how much ( fill in the blank ) they're showing. They're not aware that their cool sleeveless outfits often expose the side of their breast. They seemingly don't realize their short shirts expose their belly, which is quite an erogenous zone. In fact, my wife wasn't really aware of the seam in all her panties just to the rear of the crotch but most guys are very much aware of this as they are often afforded a clear view by tight pants and a slight lean.
So how do we address this issue with our daughters. One way is to communicate clearly with them that clothes send a loud and clear signal. They actually reflect the heart. Some will protest and say you shouldn't judge a book by its cover. But in reality, we do judge people by the clothes they wear and we send impressions to others by the clothes we choose.
So modesty is really an issue of the heart. It reflects what's on the inside. It's very important to deal with heart issues when discussing modesty. Daughters want to be accepted, in-style and not stand out in a crowd as the resident geek. And the pressures on them are enormous to conform. They need great instruction and affirmation so that they will delight in modesty.
Here are some resources on modesty that I've found helpful:
http://www.pdinet.org/sgo/v20no4/modesty.html - A great article entitled the Soul of Modesty
http://www.pdinet.org/pdf/teaching/modesty_check.pdf - Modesty Checklist, an eye-opening checklist for women to help them evaluate their clothes
http://www.familylife.com/fltoday/default.asp?id=6806&code=FRJUN03BD&cat_id=30 - A Family Life broadcast on the subject of modesty.
This website is Copyright 2003 by Nathan Martin. All rights