To add an event to the Calendar click on the Calendar button in the menu atop the forum. Scroll to the bottom of the Calendar page and a button will say Add Event. When you click this button it will pop up a topic type page. Enter in the title of the Event and Details like lvl requirement, meeting place, time, and other neccasary details. There is a pop up menu at the bottom of the post next to a bar saying Calendar on the right side is a little + click on it to expand the calendar options. Enter in the information in the provided pull down menu {date, Time, during(During I believe is the duration of the event.)} and It will post to the calendar and add a topic into the events section of our forum.
You can also navigate to the date you want the event and click on the little icon of a page on the date for the event. Adding a new event that way as well.