Put away the jeans and the t-shirts. These items are not to be worn to a college interview under any circumstances. It will send the message that you do not care about impressing the interviewer.
Buy something new. Buying a new outfit will ensure that the clothes you wear are crisp and clean and do not look worn out. A department store, such as Macy's or Sears, has a large selection of interview appropriate wear to choose from.
Stick to the basics. For girls, you should wear a simple blouse and skirt. Girls can also wear a pantsuit. For boys, a button down shirt and a nice pair of slacks will work well. All clothing should be ironed and inspected closely for stains.
Think about the colors that you choose. You don't have to stick to brown or black, but you don't want to go overboard with loud colors. Simple prints and styles will work the best.
Wear nice looking shoes. Shoes should not be scruffy and must be easy to walk in. You do not want to embarrass yourself by tripping while walking into the interview.
Accessorize with some simple jewelry. Small hoops and studs will look nice as well as a small pendant necklace. Boys should stick to just wearing a watch.