Pro Football Hall of Famer Michael Strahan is the author of Wake Up Happy: The Dream Big, Win Big Guide to Transforming Your Life. In the book, Strahan shares his strategies for suppressing the defeatist attitudes that prevent people from enjoying their accomplishments. Whether it’s playing in the Super Bowl, hosting Live! with Kelly and Michael, or appearing on Good Morning America, Strahan knows that he has to continuously re-establish his frame of mind in order to hype himself up. Teach yourself to be your biggest cheerleader and you’ll never suffer from self-doubt again.

Michael Strahan: We all doubt ourselves. I doubt myself every day. I still do. It's a work in progress and I think that's the thing about it. It's not as if you say, "I'm happy and I got it. I got the keys to happiness." But I think there are certain things that you could do, which I try to point out what I do in the book, that are triggers.

So when you realize that maybe, "I am doubting myself," that you can change your train of thought to get back on the positive side. And I think that's what it's all about. There's no secret formula in a lot of ways, but it's about recognizing when you're doing those things to yourself — how to correct them and get back in line.

I was playing a game against the 49ers, it was a Monday night game, and I had two sacks that game and I had 10 sacks on the year, which is great by football terms. And I was on my way going to another Pro Bowl, which means I was one of the best in the NFL, but I felt horrible. I felt like I was one of the worst players; didn't feel good about myself. And I went to somebody in Arizona who just reinforced that you have to speak kindly to yourself. You have to talk nicely to yourself. Treat yourself and say to yourself what you would say to somebody else to encourage them. And that's what I started to do. And next week, had a big game against the Cardinals and it was, in my opinion in 15 years in the NFL the best and greatest football game I've ever played. And I think it was because I truly told myself you can do this. You know how to play this game. You belong in this game.

And I've had to use that to do Live. I had to use it to do Fox because I wasn't so sure I could be a sports commentator, which a lot of people think is natural for an athlete to be able to do, but it's not. And then to come to morning television, I've had to tell myself that. To do GMA, I've had to tell myself that. Because I'm as scared and as fearful as anybody else to tackle something new, but I've learned that sometimes I've got to get over the fear of not doing it because I'm scared instead of not doing it because I can't do it. And I found that I was more just worried about being scared and what the repercussions were actually more than really feeling like I couldn't do something. And now by taking these chances, I feel like I can do anything. And I think once you get to the point of where you don't really care about anyone else's opinion and you really truly trust in yourself and you're willing to put yourself in an uncomfortable position, you'll find that you'll get comfortable real quick and you can do things that you'd never in a million years thought that you'd be able to accomplish. And I'm a true believer that it's all what you think of it. It's all what you think of yourself. It's all what you apply to it. It's all about the work that you put into it. And if you put all those things and you apply and you really are interested in something, then you can do it. I have no doubt in anybody. Everything is possible.