If you are not yet able to access a powerful courage state at will, the good news is that you can create a "courage part." Even if you do not feel that you are a courageous person, you can still have one part of you that acts from a place of courage.
If you do not yet have a "courage part," make one. Do a single act of courage, even a minor one. If this does not come easily, use the entire force of your will to say or do something that is difficult for you. Then presto! Your "courage part" is now a reality.
If you cannot yet do this in reality, create your "courage part" by utilizing your power of imagination. Imagine yourself talking and acting with courage. Then your "courage part" can be applied in real life.
(From Rabbi Pliskin's book, "Courage")