If you would like to keep your event hidden, you have the option to hide it from the public. You also have the option to password protect your event.
Once you're on the Event Home, click the Details tab and then the Advanced Event Settings button.
Next to the Privacy category, select Keep my event hidden, and then Save Changes.
To make an event public, follow the same steps listed above, but deselect Keep My Event Hidden so that the box is unchecked. Then click Save Changes.