Several people have written to ask what the basic daily wardrobe is for Orthodox Jewish women. Here it is in a nutshell.
First, Jewish women wear skirts or dresses only – no pants – and these must cover our knees even when we sit down. (It is advisable to test this out by sitting down in the clothes you try on in store fitting rooms before making any purchases.) Similarly, our shirts and blouses must cover our elbows even when we reach upward. We cover our legs with stockings or tights, and we do not wear open-toed shoes. Clothing can be of almost any color as long as it is subdued and not loud.
Married women keep an additional level of tznius by covering their hair completely. The hair covering is a constant reminder to the woman herself, as well as to the men who encounter her, that she has a special status; she has been sanctified to one man only and is off-limits to all others.
There are a few popular styles for hair-covering. In my community, wigs are preferred, because they cover the hair most completely. In the comfort of our homes, most women wear turbans, or a longer version of a turban called a snood. These are considered casual in my community, but in others, women wear them more frequently, to work, for example. And in other communities, hats are the covering of choice. All of these are correct as long as the woman’s hair is completely covered.
Overall, our style of dress is not supposed to draw undue attention to our bodies. This does not mean, however, that we are required to look ugly. Quite the contrary, we should appear neat and presentable. Thus, our dresses can be made of high-quality fabrics and our wigs can be combed nicely. We do not have to go around in potato sacks.
Clearly, this answer is merely a quick summary. An excellent – almost encyclopedic – book on the laws of tznius is Modesty: An Adornment for Life by Rabbi Paysach Falk. It is written in English and is clearly indexed so that you can look up a wide variety of topics in this area of Jewish Law. I’d say it’s a must have for English-speaking Jewish homes.