1: It shows that you are not ashamed of who God created you to be. : )
2: The woman shall not wear that which pertaineth unto a man, neither shall a man put on a woman’s garment: for all that do so are abomination unto the LORD thy God.
3: Dressing lady-like reminds us to act lady-like. : )
4: It shows that we respect God in modesty. 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;
5: It shows others that we take the Lord seriously and that we desire to serve Him in all that we do.
6: It’s easier to be modest wearing a skirt or dress. While you can make pants modest, it usually takes finding the right pair of pants or the right shirt to wear with it.