Preppy is a fashion style that originated in the 1950s as a way to dress in colleges. Usually this style is reflected as the snob who goes to a rich private school, but that is not the case. Many people wear this style and it gives you a nice classical, stylish look.
To dress preppy wear:
-button down shirts
-polos (collars popped up!)
If dressing preppy, do NOT wear:
-heavy makeup (less is more!)