1. In Salesforce, from Setup, enter Mail Merge Templates in the Quick Find box, then select Mail Merge Templates.
2. Click New Template.
3. Enter a name and description for the template. This will help users correctly choose a template when generating mail merge documents.If your organization uses Extended Mail Merge, choose the appropriate document type: Document, Label, or Envelope.
4. Click Browse to select your Word mail merge template.
5. Click Save to finish.