Email Preview
To access the campaign email preview, select "Email Preview" from the campaign menu:

This provides a quick preview of the campaign email. You can also see a preview of the email from the Campaign Settings - Preview Email

Documents version v.1.0.5
Documentation Menu
To access the campaign email preview, select "Email Preview" from the campaign menu:
This provides a quick preview of the campaign email. You can also see a preview of the email from the Campaign Settings - Preview Email