(Feed → +CREATE → Pin to Top)
If a Post you are sharing is particularly important and you want to be sure learners see it, select "Pin to Top" from the Post Toolbox to make it “stick” to the top of the Community. This will make your Post the first Post that learners see when they log in.
Why? You can only use “Pin to Top” for one Post at a time, but this can be a powerful way to ensure learners see your newest and most important content.