On your course page, click 'Turn editing on.' Editing links and icons appear on the page.
Click to add a new assignment OR edit an existing assignment with no submissions. The Blind Grading option is contained within the assignment settings page.
Under the Grade heading, from the Blind grading drop-down menu, select Yes.
Note: This setting will be locked once a submission or grade has been made in relation to this assignment. You must enable this setting before students submit their work.
Scroll to the bottom of the page and click Save and return to course.