1. From the object management settings for cases, go to Button, Links, and Actions.
2. Click Layout next to the social action.
3. Edit the desired fields.NoteChanging field values could invalidate incoming posts against the Social Customer Service Apex class.To send social content, the social action must have the following fields:In Reply ToManaged Social AccountMessage TypeContentImportant The In Reply To field can’t be read only.Headline and Name are required fields. To remove them, create a predefined value for each field and remove them from the action. See Set Predefined Field Values for Quick Action Fields.
4. In Reply To
5. Managed Social Account
6. Message Type
7. Content
8. Click Save.
9. From the object management settings for cases, go to Page Layouts.
10. In Case Page Layouts, click Edit next to Feed-Based Layout.
11. In the palette, click Quick Actions.
12. Ensure that the social action is in the Quick Actions in the Salesforce Classic Publisher section of the layout.
13. Optionally, repeat steps 5 through 8 for the Leads object to enable the social action on leads (from the object management settings for leads, go to Page Layouts).