Whenever you have a seriously important professional day — for example, an interview — you need to be wearing your most conservative, “notice my brains not my fashion sense” outfit. This means, unfortunately, that you need to be sure you know how the suit you wear looks from all angles. How does it look if you need to reach across a table or desk to point to something? How does it look from the back — is there a slit in the skirt that goes too high? And finally — deathly important for interviews — how does your skirt suit look when you’re sitting down? Can you cross your legs, or do you show too much thigh?
Most women are well acquainted with checking their outfit out in the mirror before they run out the door, but for interview outfits you need to go even further. Pull a chair over to a full-length mirror and sit down in it — note how high your skirt goes when you sit. If you think you might be stooping at all during the day (to pick up papers or materials on the floor), do that as well. Basically, any possible action you might take during the day should be vetted between you and the mirror, to make sure you won’t be embarrassed.