If your settings don't look like the ones below, check out this article.
Promoted Spaces give Hosts and moderators the ability to draw special attention to Spaces they want members to discover. Promoted Spaces appear in your Network navigation area with a special “star” icon that matches the Space color, which you can change in the Spaces branding.
Promoting a Space
Space Hosts and moderators can promote a Space by navigating to the three-dot menu in the left navigation menu or selecting “Promote in Navigation Panel” from the list of Spaces within a Collection. Any Space can be promoted as long the setting for “Who Can See This Space?” is Anyone in the Network.
Viewing Promoted Spaces
Once a Space is promoted, people who are not members of that Space will see the star icon next to it in their navigation. After joining the Space, the icon will disappear for that member.
Hosts and moderators will only see the icon in the navigation menu if they are not members of the Space. Hosts can view a list of all Promoted Spaces in Admin > Navigation and Spaces > Space List.