When you're ready to start developing your course, I recommend you try some of the tools and modules to get a feel for the site and how it works. Either set up a new play course available only to you or start working on the one you will use with your learners. Don't get caught up in thinking that everything has to be perfect; just enjoy it. You can delete anything you don't want, hide resources and activities (the closed eye icon), or reset your course all together.
Getting to know Moodle is essential — you should know at least the core basics before you offer the course. Start slowly and build up. For instance, if you're using Moodle as part of your traditional face-to-face class, start using core basics, like uploading content, setting up a forum, and creating links to resources. Also, be willing to learn with your learners when they get started with your course: They'll take to it quickly and may even offer you advice or give you ideas about how to extend it.