Begin by going to the calendar page: http://events.brown.edu
Near the bottom of the left menu, click on the link "Departmental Calendar Login", which will take you to: http://events.brown.edu/caladmin. You may wish to bookmark that page. You will be asked to login using your normal Brown username and password.
NOTE: There are two different login links for different types of users. General campus users should choose "add your event" or "Submit Events", but departmental calendar administrators should choose "Dept Calendar Login" or go straight to http://events.browne.du/caladmin
You should see a screen with big circular icons as menu choices.