When I first started out doing design work, there was little I knew how to do. I had the raw tools at my disposal, however: intuition, my eyes, and a knack for learning quick under pressure. My sense for design carried me through many of those first projects, and most of them involved forcing myself to learn to do the things my mind envisioned. Later, I began to take on projects without knowing how I would accomplish them. Everything I know about InDesign was learned with that kind of pressure hanging over me. Learn it, or fail to satisfy the client. Now, I could have played it safe and only agreed to work on the projects that I felt comfortable with, but that is like working on a lease.
I prefer to go places. Taking on new types of work, tackling new challenges and teaching old dogs new tricks are all things that take courage. Courage to say yes to the scary things. Courage to trust your ability to learn something new under pressure. Courage to take on risk in pursuit of a big reward.
The only thing that separates the person you are from the person you could become is courage.