I noticed that I could rank most all of my women (though not my men) students by dress (won't go into what the different costumes mean, white with head covering no veil, denim dress with head scarf no veil my favorite & I was surprised to find that for the most part these were not the best students, and black hijaab), though for the Shi'ite, who tended to prefer bare hair and jeans it was a bit more difficult: but all you had to do generally was look at the makeup and hair style though the lines were not quite so clear. Ranking men by dress was just impossible though I think the poorest men, like some of the richest, liked to wear the traditional white robes over their jeans. Some of the more religious Shi'ite also wore the robes. Others, especially those who had lived in the U.S. or Europe, often wore just the jeans, without the robes. (Some of the Iranis who come to work in the Gulf will explain it all away with the comment that "Kuwait" is "no good" but I personally think it's great to have money to get a good figure swimming and eating well and then pay a driver so you don't have to walk anywhere, seriously, it's healthier than trying to walk around there, and exercise and good nutrition are good anywhere.)
Each state actually has its traditional dress; I think the white robes and head coverings are popular in Kuwait and Saudi but actually the traditional dress of some states is a high-bodiced and fairly form fitting but not completely dress and I don't know what the head covering is. The hijaab is not part of Gulf tradition and without excessive air conditioning fueled by the oil it probably would not be possible (does it make any difference if the black garment is totally see-through and the lady is wearing a form fitting just below the knee princess-seamed print dress underneath; prints by the way are a favorite & since I like floral prints I guess my dress was o.k. there but I don't know).
Older women tended to wear a covering in almost any color but black, a head covering, and no veil, at least the poorer sort did, along with flat-heeled black shoes that were somewhat suitable for walking (where do you walk though the way traffic is set up? that is the question; hugging the sides of a roadway railing is not my idea of a nice walk but anyway; there are some places to walk though the men will notice that you are walking; maybe they don't notice very old ladies in simple opaque robes and flat black shoes). The older women did not wear face veils, none that I saw, and even show their faces in photos apparently, as I saw the face of one smiling lady from Oman (in either National Geographic or Smithsonian), decked out in her crystals that stop bad spirits, with her head covering and robe, enjoying the literacy class that her daughters had brought her to.