Each and every day, say or do at least one thing that you find difficult to say or do.
Every time you say something that is difficult for you to say, you build up your self-image: "I am a person who can speak up and say things even thought I find them difficult to say."
Every time you do something difficult, you build up your self-image: "I am a person who can do things even though they are difficult for me to do."
This is a highly empowering self-image booster. This way you will keep saying and doing things that you need to say and do, and you won't be stopped by the thoughts of, "I find it difficult to say or do, so I won't say or do it."
(From Rabbi Zelig Pliskin's book: "Building Your Self-image and the Self-image of Others" (Artscroll) Chapter 63)