From the course homepage, click on the "Grades" tab in the blue navbar. Then click on "Setup Wizard" toward the top left of the page.

Scroll down and click on the blue "Start" button. Then click the radio button next to "Weighted" Grading System.

Scroll down and click the blue "Continue" button. Choose if you'd like to automatically release students' final grade and click "Continue" again. In step 3, choose what you'd like to happen with ungraded items, missing submissions, and final grade updates, then click "Continue" again.

In step 4, choose which grading scheme (undergrad, graduate, etc) your course uses and click "Continue." In step 5, choose how many decimals (0-5) you'd like to display to students in the gradebook and then click "Continue." In Step 6 check which grade and point details you'd like to be made visible to students. Finally, click on the blue "Finish" button at the bottom of the page in Step 7.