To start giving feedback you will need to go to the assignments page by clicking on your class name.
The assignment you need to give feedback will be listed at the top. If it is not listed, check the assignment to see what time the assignment will be open for feedback.
When the assignment pop-up opens, click on 'give feedback'. The assignment will be on the left and the Feedback Rubric on the right. Fill out the rubric and click submit to take you to the next assignment.