The Client Bridge can be managed from the "Client Bridge" tab of the Contact record
To Enable the Client Bridge
Go to the "Client Bridge" tab of the contact
Under "Access Controls" Click the toggle switch labeled "Enable Bridge Portal"

If this is the first time you are giving access for this person, the "Activate Client Bridge" drawer will appear where you can set the client's unique username and password, and email address.

If an email address is provided, the system will send an automated email to the recipient with a link to the client bridge. The content of this email can be edited under the "Email Body" section of the drawer.
Click "Enable Bridge" to activate this contact's Client Bridge Portal access.