Hearing how Gen. Stanley McChrystal flubbed the Rolling Stone article about him reminded me of something I’ve been meaning to say here, based on my experiences as an interviewee and interviewer.

A few years ago, my PR company insisted that I train with a coach for an interview they set up for me on GMA.

“Why?” I said. “I spent a year of my life building, launching and talking about this site. Isn’t that enough preparation?”

As soon as I got on the set I realized why they recommended training. A TV interview is different from other conversations. When I talked about my site to an advertiser, I had plenty of time to refine my pitch. I could even schedule a follow up call.

On TV, there are no do-overs. Plus the lights, cameras, and attention are all unlike a regular day at work.

The only reason I was able to respond to the tough questions is that I listened to the advice I got and did mock interviews for practice.

I ended up doing okay (we got about 250,000 new registrations), but I could have done better if I had the advice I’m about to give you:

Give as many interviews as you can throughout your career, even if the audience seems is too small. Do it for practice, if for no other reason.

I’ve interviewed over 300 people on Mixergy. I can tell who’s never done an interview before — and so can my audience. I’ve had guys get key info wrong — like the names of their companies — because even a little web cam can bring out nerves.

It’s fine on Mixergy because my job isn’t to provide polished entertainment to the masses in between shampoo commercials. So if you’ve built a great company, use Mixergy as your platform to start talking about it. But if this isn’t the right fit, talk to Giang, or Gabriel, or David. Or have someone in your office interview you for your company blog.

Don’t wait till you get to the World Series before you pick up a bat.