During the creation of the course, it is recommended you don't allow learners access before it is ready so they don't see an incomplete course.
In order to do this, access has to be restricted by going to the course Settings tool:
Illustration 17: Course administration tools
A series of choices are available to the teacher.
Illustration 18: Course settings - Visibility
Public : means it is accessible to any user, registered on this portal or not
Open : means all users registered on the portal can access the course as long as they have previously subscribed to it (they can do this through the courses catalog). This is the default option
Private : means the course is only available to students who have been subscribed to it by a teacher or administrator. Make sure the Subscription option is set to be only available to trainers, though, as otherwise students might be able to subscribe themselves.
Closed : means the course is only available to its teacher or the administrator. Other users cannot access it, even if they have previously been subscribed to it. This last option is recommended during the building or maintenance periods of the course.