To change an events status - go to OPEN EVENTS and click the icons on the left hand side.
Private = Event is not listed online. Only accessible via unique event URL.
Public = Event is in public mode and is searchable online.
Offline = Event is not listed online and not sellable.
Cancelled = Event is in a cancelled state. It will show online but will show that the event is cancelled status.
This video will show how to put an event in private mode. This can also be used to see how you would put an event in public mode.