Tony Robbin's makes sense in his article "Master Your Emotional Health And Master Your Life" (click on picture to get to Tony Robbins).
He talks about three important aspects: Physiology, Language, and Focus.
Physiology - Tony talks about slumping and bad posture which I unfortunately sometimes engage in. I think learning to put your shoulders back, standing up, and not slouching can most certainly put you into a more positive state.
Language - language, language, language. This is essential. Spin situations, no matter how challenging, into positive and potentially life learning scenarios. I definitely see the advantages of turning this into habit.
Focus - Don't pay attention to fear. Pay attention to positive things you want and a positive end state. Living in fear or apprehension does nothing. If you drift to worry drift to safety and positive affirmations.