Matthew,
My answer would sit somewhere between Mike and Martin. Yes, how you communicate your ideas is very important. You need to explain to people what you see in your mind. But putting it on paper makes it clear for everyone what you are trying to do. It is "the" universal language of course design.
Doing CAD work is important if you need to do plans yourself. But being able to draw in 2D, or better yet, 3D, will help you a lot more to start with. The CAD stuff is easy to learn, once you know how to draw what you want to illustrate with the CAD software. Understanding scales and contour maps is also an art that can learned through practice and that will be extremely helpful. So is drawing.
Just study all the golf course drawings you can find, and try to create a style of your own. A style you will be able to use to clearly communicate your ideas. And then, practice, practice, practice. "Routing the Golf Course", by Forrest Richardson, has a good number of different plans that are interesting. So does many other golf books.
Good luck,
YP