Morning Glory: How to Dress for an Interview

This post might be a bit of a stretch, but oh well. I just finished reading the book adaptation of the new Rachel McAdams' movie "Morning Glory." I really identified with it because she had to prove herself in a world of Ivy League graduates like I will have to if I get in the fashion industry. The book was super cute and I can't wait to see the movie.
This post is going to be all about job interviews. But mainly how to dress for them:
My friend Katelyn went to a session at the CMA conference we just got back from about how to prepare for interviews. The speaker told her how to sit (good posture with your hands in your lap) how to walk (people judge you within seconds of seeing you) and how to dress. The tip that stood out to me the most was not to rummage around in your bag for things, but be organized.
The following tips are what I have gleaned from talking to various guidance counselors and the people who work at the career center here at my school.
-Dress up more than the people who work at the office you are interviewing at. For example if you are interviewing at a law firm you would go all out. Pantsuit, high heels, and a sensible bag. If you're interviewing at somewhere casual I would do this: stay classic, but bring in some trends to show that you can be creative, but sensible. Here's a budget friendly outfit idea.
Forever 21 Kitten Heels

Line & Dot Silk Pleated Bow Blouse from Urban Outfitters

A classic blazer. Target has one for about 12 dollars.
I would probably pair black pants with these pieces just to keep it from looking so date like.
Just remember don't look like you could go to the club or the beach in what you are wearing! And I would say no to even fancy jeans. Use your common sense. Would you hire yourself in what you have on?