Unlike many Far East countries, where saving "face" is important, in North Korea if you insult a person instead of them feeling shamed, you are expelled from the country and the person you may have inadvertently offended may be sent to jail for being the recipient of your comment so be weary of what you say. Also remember that if you're on a tour and make any insulting comments or ask unwelcomed questions your tour guide may be punished or even imprisoned for your lack of understanding so keep your opinions to yourself until you leave the country. Fortunately, this tour guide will also help you navigate the complicated social requirements and laws so take their advice to heart and always follow their advice and rules.
Dress
The traditional dress in North Korea is called choson-ot (which simply means "Korean clothing") and has existed for hundreds, if not thousands of years. This clothing is very simple in style and design, but is often quite colorful. For women the top was generally a long-sleeved blouse called a jeogori, with a jacket and a large skirt called a chima. For men the top shirt is also called a jeogori, but men traditionally wore pants called baji, which are very loose-fitting. Historically, the color of a person's clothes indicated their social status as commoners generally wore white, but for special occasions numerous colors were worn.
Today the traditional clothing of North Korea rarely seen outside the "Mass Games," which are essentially just a giant performance for the country's leadership to pat itself on the back. More commonly today, the people wear western-styled clothes, much of which is simple with no design pattern, other than for specific uses, like military uniforms. The clothing is generally dark in color and simple enough so no one stands out from anyone else.
As a visitor to North Korea, you must be aware of the many odd restrictions in the country, both in the way of dress as well as in numerous other areas. The first dress restriction, if that's the correct word, is that men are expected to keep their hair no longer than a couple inches in length so be sure to get a close haircut before arriving. For women, pants were outlawed as long skirts are the cultural norm so visitors may want to purchase a few of those prior to arrival (although this rule seems to have changed in recent years). Most importantly, don's wear anything that can be perceived as offensive to the government or people. Since the government can decide something is wrong or offensive at any time, try to avoid wearing anything with any words or pictures on it. In general, most foreigners are only allowed into the country with a government-issued tour guide; check with your tour company before arrival for an updated list of dress restrictions in the country or you stay may be very short.