Once you have registered for a course and clicked the "View Course" button on your Dashboard page, you will arrive at the Course Info page. This page contains announcements from the course staff and Handouts that you may find useful.
To get to the course materials, click on the Courseware tab on the top left of the page:
The Courseware page contains a list of sections on the left-hand side. Click the first section to expand it, then click a subsection to open it. You'll end up with a page that looks like this:
You can use the small left and right arrow buttons (in the red circle) to move to the next or previous page in a subsection. If there is only one page in the subsection, these buttons will be disabled. You can also use the navigation bar (in the red box) to skip forward or back – just click on the little icon of the page you want to go to. The page you're on currently will be in white on the navigation bar, and all other pages will be gray.
Once you have finished with all of the pages in a subsection, pick the next one from the list on the left (see the red circle below).