Click on "Calendar" (the link is not obvious, so use your browser's find functionality to search for the word "Calendar"). Edit: Please use the ⇧Upload⇧ link in the menu bar
Choose a slot
Submit your email address
Click the link in the confirmation email
Create your profile (if new), then fill in the form with title, summary and show notes
Attach your episode and submit (wait for long upload process)
Receive your confirmation email, and enjoy your episode!