So how do you speak on a live TV interview?
Live TV is something that scares people. Scares them more than almost any other type of interview. The reality is a live TV interview is the safest, easiest type of interview because you don't have to worry as much about quotes and sound bites being floated out of context in a way that makes you look bad. Because the whole interview is there live for people to see. So never, ever turn down the opportunity to do a live TV interview.
That's why so often you'll see politicians tell a show like 60 Minutes, "I'll not do an edited interview but I'll do a live interview." Because it's easier to repeat your message and get it across.
Now, if you're doing a live interview and all of a sudden you, "Ah, cut! Can we do that over?" No, you can't. You don't get to be the director. You can't say cut. You make a mistake, you stumble a little, you just keep on going and make the best of it. You can't obsess and micromanage your own performance.
The other thing when it's a live interview, or a taped interview, the best thing to do is just look at the reporter. Ignore the cameras. Don't play the cameras. Talk to an actual reporter. Now, if there's no camera around and you're listening to an earpiece, then you look at the camera. But, in general, look at a human being and you'll be much better off.