Report and Dashboard Folder Sharing has many layers and settings, both on the User Profile and at the individual Folder-level. The sharing method shown below is for a system that does NOT have Folder Sharing Enabled.
Navigate to the Reports Tab. In the Folders sidebar menu, hover over the Folder you need to grant access to. Click the dropdown arrow and select Edit:
Here, you can select to have this folder accessible by all users, hidden from all users or make the folder accessible only to selected public groups. See also: Creating Public Groups.
In the Available for Sharing column, select the Public Group and click Add to move the Group to the Shared To side:
Again, this method is used by companies that do NOT have Folder Sharing Enabled.
There are additional Sharing Options available to organizations with Folder Sharing Enabled. Keep in mind, once you have Enabled Report and Dashboard Folder Sharing, you cannot revert your system back. The change is permanent! Please review all related Articles below, before Enabling Report and Dashboard Folder Sharing in your system.
See also: Enable Report and Dashboard Folder Sharing
See also: Report and Dashboard Folder Management - Profile Settings