Dress for success
Survey: Work Clothes Speak Volumes About You
This survey says that casual clothes make people think and relate more to you. So it depends on what image you want to convey. When I worked as a Jewelry Specialist at Kohl's, I would wear dress slacks and a long-sleeved dress shirt. People would routinely mistake me for a manager.
There's something to be said for casual Fridays.
But something is lost not only on Fridays, but if you were casual clothes every day. There is something about wearing working clothes you don't wear in leisure time that adds to your attitude. When you put on the fancy duds (even a tie if need be) you're stepping into your role. You look yourself in the mirror, and even subconsciously throughout the day, your clothes are telling others and you that you are at work.
When you get home, you shed your work persona like a snake sheds skin, and can step back into being you again.
But if you want advice from me, ONE dress nice and TWO don't dress nicer than your higher-ups. And, oh yeah, THREE, if you work at a construction yard or a related field, skip the dress shoes and grab the steel-toes, okay?