Adding an announcement to your community can be done easily in portal setting. Only admins and community managers can post an announcement on the community. In the example below, we made an announcement with a title "Empowering the new generation of online branded communities" to promote our product, Tribe. We made the action button "Create your tribe" to direct the user to our website pricing page:

Follow the steps below to make an announcement on your own community:
Admin Panel> Settings> Announcement> Define content for the announcement, choose a name and a link for the action button, choose the picture and the layout> Enable> Save.


If you have a question regarding this tutorial, add a comment on this answer.
Here is the recommended size for the picture in announcement: 1240 x 800 pixels
The recommended width is the minimum of 1240 pixels.
The height of the announcement depends on the amount of content you write within it as the box stretches out so we recommend a height of no shorter than 800px.