When you create a new event that event stays in Draft state until you change it to Publish state. In draft state you are not able to send out tickets or app invites and your attendees can't join the event in the app. Only attendees who are labeled as organisers can receive tickets and app invites and access the event in the app.
To change the state of the event to Publish simply go to Overview on the left menu and click on the button Publish event in the Event visibility box
You can of course revert back to Draft if you wish, by clicking on the button Revert to Draft State in the same box.