The Event Selector allows you to work on multiple events at the same time whilst making use of all the full range of features available to them.
To do this, locate the 'Current Event' selector underneath your logo (as shown in the picture below).
Then, click in the dropdown box. Begin typing the name of the event and you will be presented with a list from which to select:
Once you have clicked your event it will be bold within the event selector (see below).
Please Note: Make sure you have the correct event in your Event Selector before you start making changes.