How It Works
When someone creates an event and invites you to attend, you will get an email with a link to the event, like the one shown below:
Click on the link to see more information about the event and to RSVP. The page will look like this:
When you click change, you will see this:
Choose if you are going or not, add additional guests if needed, then click save.
Getting There from the Calendar
You can also RSVP for an event by clicking on the event from the calendar. If you have the "manage_events" privilege however you are going to see an event form first. To get to the RSVP form, you just need to click Details & RSVP and it will take you to the event's detail page.