It can consist of wearing masculing clothing, a bear and mustach, breast binding, shaving ones head, acting masculin etc... Some do it as a form of performing art, also incorporating dancing and singing. Others may use it as a way of expressing themselves, having fun or simply walking around like that.
You might have seen Lady Gaga dressing up like a man.
The first popular male impersonator in U.S. theater was Annie Hindle, who started performing in New York in 1867. British music hall performer Vesta Tilley was active in the late 19th and early 20th centuries as a male impersonator. http://en.wikipedia.org/wiki/Drag_king
Drag kings are said to be largely a phenomenon of the lesbian culture and can most often be seen at lesbian bars. But not all drag kings are lesbians.
This can be a fun way of expressing yourself and realizing you do not have to fit into the cultural stereotype of what it is to be a good "woman" of "man". If people judge others according to those standards, it shows their own brainwashing and cultural indoctrination.What a female or male should look or act like has changed through the years. And really: who can decide this? And more: why would we obey to this?
What is our constant obsession with judging others when they do not fit into the picture we desire from them?
It is important to look at our starting point with whatever we do.
If one does this because of dissatisfaction with ones body , it is important to get to the root of why one feels like this. If we feel inferior, depressed, disgusted or sad about what we look like, then there is a problem involved. Because you are harming yourself through judging your physical body. While we could be comfortable within it no matter what we look like. This is the same as others judging you as being a "good" female or male, you are now judging yourself as less or more. And what exactly are those thoughts that make you think like that? Why did it start, when and why do you allow it? If you give it power over you in that specific area, there is no certaintly that it won't come back in other areas. You may be able to dress differently, but that has not removed the source of the problem.
If a woman wants to shave her head, then she can do that as much as a man. If a man wants long hair or wear a skirt, then he can do that as much as a female. Why would our genitals decide which clothing we have to wear, or how we have to speak and behave, or with which toys we should or should not play? It is actually more the general look that people judge wether you should act and look like a male or a female. Female face = act like a female.
Dressing like a female, a man, an elephant or a lepracon... can be fun, a way of expressing yourself. But we have to be on the lookout of hidden insecurity and judgement. And make sure others judgements do not become our own.