This assumes you have navigated to Announcements. Click Announcements to populate the list of Feeds.

Double Click the Announcement Feed.

Hover over the line item and click Notification.

Enter a Notification message and click Send Notification.
Pro Tip
"Test Message", if selected, will only send to Test Devices and not the subscribed population.
"Schedule Message" populates a Date and Time field for delayed notification deployment.

TO ACCESS Content Explorer:
sign in with a privileged user
from global navigation
select Content Explorer
select Activities, Trips and Classes
- select a Announcements