Establish a sense of style. Your clothes and how you wear them say a lot about you, and will have an effect on how people perceive you. Wearing unflattering or extremely poorly-sized clothing says you don't care about how you present yourself. The particular style is not as much a factor as how you wear it. You can wear whatever style is comfortable for you, whether it be trendy, alternative, casual or sporty, as long as it's appropriate to who you are.