Set Up LiveMessage with a Guided Setup Flow
Where: LiveMessage in Lightning Experience is available in Enterprise, Performance, Unlimited, and Developer editions with the Service Cloud. This feature is available in orgs with access to LiveMessage through a Digital Engagement add-on.
Who: Users with the System Administrator profile can run this setup flow. To run the flow, the org must have the Service Desk and LiveMessage permissions. There must be available LiveMessage permission set licenses and Service Cloud User licenses in order to assign users to a queue if one is created during the flow.
How: From a Lightning Experience app, click the gear icon, and select Service Setup. If you don’t see the LiveMessage setup flow tile in Recommended Setup, click View All. Select LiveMessage Setup.
Alternatively, go to Setup, enter LiveMessage in the Quick Find
box, and select LiveMessage Settings. Click New
Channel to open the guided setup flow and set up your channel.
When you set up SMS, we provide the steps for sending Salesforce a letter of
authorization that allows LiveMessage to send messages from your phone number. After
your phone number is enabled, complete the setup in the LiveMessage Setup page. 
When you set up Facebook Messenger, you can optionally create an Omni-Channel
queue for your incoming messages. Run the flow multiple times to enable all your
company’s Facebook pages with LiveMessage.

