Elder Tad Callister said it best in his devotional address at BYU-I entitled The Lord's Standard for Morality
Women, I took the liberty to look for some nice modest clothing in which you can feel good and care about yourselves in the way that is pleasing to the Lord. Here is what I found.
"Our dress affects not only our thoughts and actions but also the thoughts and actions of others. Accordingly, Paul the Apostle counseled “women [to] adorn themselves in modest apparel” (1 Timothy 2:9).
The dress of a woman has a powerful impact upon the minds and passions of men. If it is too low or too high or too tight, it may prompt improper thoughts, even in the mind of a young man who is striving to be pure.
Men and women can look sharp and be fashionable, yet they can also be modest. Women particularly can dress modestly and in the process contribute to their own self-respect and to the moral purity of men. In the end, most women get the type of man they dress for."
Women, what message do you want to send to the young men? You don't want to send a message that you don't care about yourself by dressing immodestly. That is what happened to one young woman in the YSA ward in my Stake. He took the advice to marry quickly to heart and decided to date all the girls in the ward. However, one girl he refused to date because she was dressed immodestly and from that, he knew she did not care for herself. She missed out on a date from that righteous priesthood holder.
The Lord has never deviated on his standard for the way we dress. It has always, and will always, remain the same. Think of the sacred garment. Has it changed througout time? No, it has stayed the way it is now since Adam and Eve and has not changed to suit the fashion of the day. Young Women need the practice of wearing clothes that would cover the garment once they go through the temple with a worthy priesthood holder to be sealed.
Please listen to the thoughts Sister Julie Beck has on this topic:
Julie Beck Q&A about Modesty