Hair:
Should be clean and neat.

Shoes:
Should be in polished condition. Make sure heels are not worn.

Details:
No missing buttons, no lint; and don't forget to remove external tags and tacking stitches from new clothes.

Hands:
Clean fingernails.

Fit:
Clothes should be clean, neatly pressed, and fit properly.

Smell:
Perfume or cologne should be used sparingly or not at all. No odors in clothes. Don't smell like smoke.

Pad folios:
Preferred over a bulky briefcase. A small briefcase is also appropriate. But if you have no reason to carry a briefcase, don't; you risk looking silly.

Book bags:
Leave it at home for an on-site interview. For an on-campus interview, you can leave it in the waiting area.