A Peer-to-Peer Assignment is an assignment that is built out of a question or a task. You are either requested to insert your answer in a text field or you need to upload it as a file. Your answer will be evaluated by seven of your colleagues afterwards.
After you have entered your answer you have just the option to save it. Your answer will be automatically submitted at a defined submission date, even if you haven't typed in anything. In this case a blank text will be submitted. So make sure that you write an answer before the submission date is due.
Shortly after the submission date you will receive an email notifying you that the peer evaluation is open and that it is time to score your peers' answers. Please keep in mind that you have to score your colleagues answers during the exam period wich is determined by the course instructor.
Go to the peer to peer assignment again and click on "Start Scoring". Now you have to grade and comment seven answers of your colleagues.
Once the evaluation period is over you will receive your result for your own answer. If you are unhappy with your grade, you can submit a complaint. If the professor feels you have a legitimate complaint, your assessment answers will be re-graded.