It's not just what you display on the outside..

the inward appearance matters as well.
It's easy to dress modestly and act godly, yet look rotten on the inside. (Think of a shiny, beautiful, perfectly-looking, pear. You bite into it and realize that it's not what it seems. The inside is rotting and little worms have found their abode.)

 i.e: there can be a young lady who dresses very modest, but she isn't serving the Lord with all her heart. She disobeys her parents, loses her patience easily, and in fact, when she isn't in church, it's hard to tell whether or not she's a child of God.

Examine yourself. What are your virtues? And what areas do you need to work on? Think about it.

scripture.

"In like manner also, that women adorn themselves in modest apparel, with shamefacedness and sobriety; not with broided hair, or gold, or pearls, or costly array; But (which becometh women proffessing godliness)with good works."

1Timothy 2: 9-10

Heart/Wardrobe Check!

-Do I have a humble view of myself and a high view of God?
-Do I avoid promoting or advertising myself?
-Am I free from extremes of behavior and personality?
-Am I grieved at the thought of offending God or causing someone else to sin?
-Am I appropriately reserved in speech, or do I talk too much?
-Do I always have to be the life of the party or center of attention?
-Am I free from showiness and ostentation? (being forward, arrogant, aggressive, controlling)
-Am I appropriate in behavior?
-Am I appropriately reserved in the way I dress?
-Do I wear "respectable" clothing? (1Timothy 2:9 "respectable" means orderly, decent, not causing distraction or temptation.)
-Is there writing or pictures on my clothing that emphasizes certain parts of my body? (If someone were to look at me, where would their eyes go naturally?)
-Is the fabric that I'm wearing too sheer? (Could someone see through it to certain parts of my body?)
-Am I wearing tight, form fitting clothes?
-Am I wearing anything provocative?
                      -Nancy Leigh DeMoss

wise words concerning modesty:

"Modesty is not first an issue of what we wear. It's essentially an issue of the heart."

Ask yourself: 
"Am I helping or hindering men who desire to be morally pure?"
"How can my dress and appearance bring glory and help my brothers stand?"

Our culture shouts,
 "Be cool"
 "You only go around once."
"Go for the gusto"
But the Lord whispers,
"You only have one life; live it for My glory."

What would it mean for you to dress for the glory of God? 
Would you need to make any changes in your wardrobe?

Before we point our fingers and criticize and judge in our hearts, let's say, "What can I do to encourage this woman in her walk with God?"
Remember: modesty starts in the heart. It's a heart issue before it's a clothing issue.