Arrive on time. Dress well. Write a thank-you note. Don’t lie on the application. You have the job-hunting basics down, but the gods of employment have plagued your people with a drought. Whether you’re interviewing after a layoff, seeking a change of employment or documenting your futile interviewing plight to milk yet another unemployment check, be aware of these five deadly interviewing sins.

1. Don’t get too friendly. You’re chatting with the interviewer, discussing professional experiences and swapping war stories; however, a relaxed interviewing environment is no excuse to become complacent in your professionalism.

An ex-colleague of mine was looking to migrate back towards substance-abuse counseling, his original area of study and expertise. He was cordial, outgoing and a hard worker. He had plenty of experience and great references, but he met his downfall while making small talk. After the interview, the hiring manager mentioned in passing that he had recently received a DUI. My colleague, attempting to empathize, admitted that he, too, had received a DUI ticket. On three separate occasions. Lesson learned: get job first. Tell war stories later.

2. Don’t forget to train rigorously. Reading job-seeking books, articles and studying potential interview questions are all great ways to prepare, but these resources don’t exactly put you in the interviewing hot seat. You wouldn’t expect to run a marathon just because you’ve read several books about running, would you? Get a friend or significant other to give you a dry run through a hypothetical interview with suggested questions from these books or articles. Even better, if you know someone who is a hiring manager or works in human resources (for a different company, of course), ask them to administer the mock interview.

By humbling yourself and asking for the help of others, you’ll receive constructive criticism and be able to integrate another perspective into your response. You may even be asked a question that you never considered answering, making great practice for unexpected interview surprises.

3. Don’t forget to shut up. When you’re done answering the question, shut your mouth. The two deadliest kinds of interviewers we will refer to as the “poker face” and the “yes man.” The poker face will ask you a question and give no signs of life during the answer. In hopes of eliciting a smile, nod or comprehending grunt, you will elaborate. And elaborate. You will continue elaborating until you realize that the poker face is playing a game. By the time you realize you are involved in a game, you have already lost. Take this knowledge and answer the next question completely, concisely and without superfluous commentary.

The yes man is just as deadly, if not more so, than the poker face. He will nod his head and seem to understand and agree with every answer. Feeling encouraged by this enthusiasm, you will elaborate. And elaborate. You will continue elaborating until you realize that you could say your career goals to sleep with the boss, publish trade secrets and burn the building down, and the yes man would still nod his head.

In the yes man’s defense, sometimes he may actually agree with what you are saying at first, but, towards the end, every nod means “Yes, I understand. Just like I understood ten minutes ago. Please stop talking, lest I puncture my own eardrums with this letter opener.”