News Feed is enabled by default.
Open news tab in the left navigation.
Click on Add news button in the top right corner.
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In the new window you can add new information:
Add post title.
Add content.
Add a preview image, youtube video, or upload your own.
Note: if you want to upload video file, make sure it is less than 15 MB.
You can also pin the news to the top so everyone is aware of some changes.
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Save your post.