A Submit an Event button can be added to the header of Calendar pages.
Users who Submit an Event will be provided with a drop-down menu listing each of the Calendar categories to which the user has View permissions. This list can not currently be edited other than by adding or removing the View permissions from specific Calendars. Users can be required to log into the site before submitting Events or the option can be made available to Guests of the site.
Once an Event is Submitted, a back-end user with Publisher or higher permissions for the associated Calendar category must approve and publish the event before the Event will display in the Calendar.
To enable the Submit an Event button and add Public Submissions to your site, contact Support.