To highlight an important post in a Google+ community that you own, pin it to the top of the page.
Pin a post
- In Google+, from the main menu, click Communities.
- Open your community.
- Click the post you want to pin.
- Click MorePin to Community.
Any incoming posts will appear below the pinned post.
Unpin a post
- On the post you want to unpin, click More Unpin from Community.