After sending out all of those letters and networking like crazy, you finally got the interview. You are prepared. You have your résumé printed on good paper; and you have studied your background so you don’t have to play the total recall game. You won’t worry about being able to match Charles Nelson Reilly with Gene Rayburn looking on http://en.wikipedia.org/wiki/Match_Game. The big day is coming - what do you wear? You know the company is a casual place to work. Do you dress up, down, or somewhere in between?
Since you are not yet an employee, the best thing to do is dress to impress. I understand that the company is a laid back atmosphere, and people can show up in jeans and flip flops. That’s fine - for those that are already employed there. You are TRYING to get employed; so, you need to dress differently than the people that already work at the company.
For the guys: Wear slacks in a dark color and a button down shirt with a collar and tie. You should wear a jacket too. The only caveat to this is that if the company is a start-up, extremely entrepreneurial, and the staff very young and hip, leave off the jacket. You don’t want to come off as stodgy or un-cool in some way. Part of what you are assessed on during the interview is fit, so dress is part of that. Otherwise, wear the jacket. You will look like you mean business. You will have plenty of time (and clothing, no doubt) from Hollister to get you going once you have your offer letter.
For the gals: Wear a pant suit or skirt suit with an appropriate blouse or top. Do not wear anything that is sleeveless. You can also wear a dress. No open toe shoes please. Keep it professional. Long hair? Tie it back to keep it neat. Last time I checked Barbarella http://en.wikipedia.org/wiki/Barbarella_(film) was piloting a space ship not an Excel spreadsheet. Again, I would suggest something on the conservative side. Heels are fine; in fact, I prefer them, as long as they are not 4″ high. You want to be comfortable; but more importantly, you want to be able to walk. Finally, I am all about nicely done nails, as long as you don’t look like Vampira. Keep them neat with a conservative color. If they can be considered for the Guinness World Book, how will you do any work? Everything counts. Believe me, you are being evaluated from a number of different perspectives.
All joking aside, personal appearance is very important during the interview process. Your outward presentation gives off signals. Make the most of yours by dressing to impress!