Most of the rules obviously apply to TV interviews but there are a few distinct things to bear in mind.
1. If you have to pay travel expenses (airfare, hotel, and food), you need to decide if your exposure justifies the cost. TV interviews on channels with commercials means the interview time runs five to eight minutes, although some are as long as eleven minutes. (And that will vary.) Sometimes I've had eleven minutes, sat through a commercial, followed by eleven more minutes of interview. And I've done double-eight-minute interviews.
Is it worth it to you (or can you afford) to spend up to $1,000 for a few minutes of exposure?
2. Dress appropriately for interviews, and for women, especially, don't overdress. When you receive an invitation, most of the time, you'll receive information on what not to wear, such as a lot of white.
Besides that, I suggest you dress conservatively. How would you dress if you went for a job interview? No matter how informal my hosts, I wear a tie. (If I feel overdressed, which I did only once), I can take off the tie and open my collar.
2. Look at the host while talking. Ignore the camera unless the host says, "Please look directly into the camera and tell our folks at home . . . " That has happened to me a few times. Otherwise, keep your eyes on your host.
3. Always carry extra copies of your book and a copy of your suggested questions. One TV station on which I've appeared nine times has revolving hosts, so I don't know who will interview me. That's not a problem, but it means that the interviewer may not have the book or questions. You can graciously provide them.
4. Bring one or two extra books to give to other guests—if you think they'll appreciate them. I also give them my business card or a bookmark with my contact information. I can think of two occasions when another guest has contacted me later.
5. If you're comfortable doing so, hold a copy of the book in your lap. If the hosts don't hold up the book for the camera, you can do it when you're talking. Just hold it up as you talk, and make sure they can read the cover.
6. Smile. I'm amazed at the nervousness of some authors who are so tense it's as if their faces froze five minutes before the interview began.