No matter how gorgeous you look, if you walk like a man, you will give yourself away.
When I first started going out en femme, I looked ok for a novice because I had been experimenting with clothing and makeup for a long time, but I had never been out of the house (except for Halloween). As a result, I walked like a man because there was no need to do otherwise dressing in the confines of my home.
My girlfriends admonished me, so I began to make a conscious effort to walk like a woman. After years of practice, it has become a second nature. When I am en femme, I find myself walking like a woman without making a conscious effort to do so. It is part of putting on my game face when I get dressed, i.e., a part of switching into girl mode.
So, how does one learn to walk like a woman? Instead of taking the time to explain how, I direct you to the following links that explain how: