When creating a group, you can select Enable external access
to turn a community group into a place where standard users can invite external contributors
to extend their communication and collaboration to the outside world.
To create a group with external access:
Click > Group.
On the Create group page, enter the group name and details.
Select Private or Secret for the group type. External groups are limited to Private or Secret groups to
help protect community information.
Select Externally Accessible to allow external
contributors to be invited to and join the group. Externally Accessible groups
must be private or secret. You may not see this option if it's not enabled for your community.
Click Advanced options for more options.
Click Preview > Create Group.
If you see the Invite People to Join dialog, then add a few users who you want
to invite to the group, and click Send Invitation.
To manage group features and select the storage provider, select Manage > Settings
Click the gear icon in the Group Features and Activity tile.
Select or unselect features for the group. People will be able to create the
kinds of things you select.
If available, you can select a storage provider for storing your uploaded files.