Make sure to send the person who interviewed you a thank you page after you're done with your meeting. This can make a good first impression in case you didn't make one during the graduado en eso interview you had.
Do some research around the hiring firm, about their line of their income and business, before you go for the appointment. Making your interviewer realize that you've done some research can show him your motivation to locate information and getting results. These are excellent characteristics of the inspiring and reliable employee that companies value.
A terrific suggestion for workplace harmony will be to avoid associations at work, and if you are the company, have a policy against it.