Create a new list
If you enable reading lists in Canvas and there no reading list associated with your course already you will see a screen like this:
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When you click "Create new list" you will be taken through the steps to create a new list associated with this course. You'll give the list a name and a description if desired. You will be able to select from a list of templates with pre-built sections for organization (which you can change later). And then you will be able to start adding items to your list.