You can edit your course settings by clicking the 'Edit' button in the Manage Courses page underneath the course you wish to edit. You can also click the 'Edit' button when viewing a course page or a courses grade page.
You can only edit the settings for courses you've created. If you joined a public course you will not have access to changing any of the settings.
Right now, you can change the course name, number of credits, days of the week the course falls, and the Assignment Types. Make sure to click the save button before exiting the page if you've made any changes.