Affirmations are a powerful tool for self change and self-actualization.
For best results using affirmations speak the affirmation out loud at least three times daily, in the morning, mid-day, and at night. Repeat daily for at least 30 days. When speaking affirmations, say the affirmation multiple times each session. Some suggest saying it as many as 10 times each time you speak it. I believe a minimum of 5 times is necessary to get any real effect.
Below are some resources for working with affirmations: