By default, when you create an event in your campaign, it will be set to draft. 

1. You can toggle it to "Published" mode by clicking on the button that says "Draft" on the event.

2. To change an event from "Published" to "Draft" click on the button that says "Published" on the event in the campaign event list.

3. If you want to change all of your Events from Draft to Published at the same time, choose the link at the top of the list of events that says "Unpublish/Publish All".  

Note: Whether you see Publish all or Unpublish all at the top of the Event list will depend on the status of the first Event in the list.