Within 360Alumni communities, any user can create an event. If you wish to create a 'free' event, take a look at the following steps.
There are 3 event types.
To create a "Free Event," simply navigate to the events tab/page and click on "Create an Event." On the first step of the event creation process, check the "Free Event" button on the bottom of page under Ticket Options. This will essentially pre-populate a free ticket type with a price of zero on step 3 of the event creation process. User's wishing to attend this free event will still need register, so that they appear as event attendees.
For a more detailed walkthrough, please refer to the "Create an Event" article.