Start by providing some essential details, such as a descriptive name, the core message content, and key settings. 

• Name – Provide a descriptive name indicating the message purpose e.g. "Priority Case Assignment".
• Developer Name - The developer name is automatically generated, but can be edited on creation. This unique name is required to post Act On It alert messages using flow and apex.
• Default Message Content – Enter the core message text to display. This appears in the preview so you can validate how it will look to recipients.
• Additional Details – Optionally add extended message details, help text explaining the alert, and a description of where this message is used.
• Tip: In description, note any dependencies on this message type to prevent inadvertent deletions.
• Data Type – Link to a specific Salesforce object like Opportunities or Cases to surface relevant actions. Leave blank for universal messages.
• Release Status – Live to activate now or Trial Mode to test without impacting users. Trial messages will be recorded for reporting purposes, but not delivered.
• Display Location – For alert messages, show in inbox, on records (guidance console), or both locations.
• Expiration – Optionally set a lifespan after which the message disappears, for a self-managing inbox. Useful for time-sensitive alerts.
• Sender – "Customize Sender" allows you to set a custom sender label like "Act On It", "System" or "Customer Portal" instead of the running user.
• Category – Categorize messages (assigned by admin) to allow inbox filtering by type, priority or category.

Once you have configure your Message Details, click "Next" to continue.