At the top of the page you will find:
FAQ: About this system (NOT SUBMISSION!)
Search: Search within this system (e.g. to find a special message)
Profile: Your profile (email address, phone, etc.)
PM: Your personal/private mailbox: Here you can write and receive messages that ONLY the recipient will see
Log out: When you click here, you will have to log in the next time. You can also simply close the window so that you won't have to log in again when you come back the next time.