A lot of my clients always ask me what should they wear to their session. As a general rule of thumb I always say wear what makes you comfortable. That being said, the results aren't always the best so I decided to post several articles on complementary colors. Test yourself by closing your eyes and think about your favorite color and see what type of discription it gives you. Also consider using the The Basics of Color theory when selecting your favorite spot to shoot and the colors you decide to wear.
As a general rule of thumb you don't want to have more than three colors in your outfit. Use the right colors for your skin tone and coloration is key in ensuring that your images have the right amount of color and pop that you see if a lot of your high fashion imagery. Try different colors against your skin and learn which palettes look best on you. Also, get a second opinion. Unless you are shooting for the holidays, stay away from colors like red and green. Avoid matching gray colors with bright colors such as yellow.
Please note on the psychology of color chart published by graphic designer Carey Jolliffe the range of colors and their associated moods on the referential chart.
Here are several links that explain in a simplified way how to choose colors for your session.
The Basics of Color theory to know what looks good was published by LifeHacker.com
Color Schemes via Color Wheel published by Tiletramp.com