Preview your campaign in the email composer. Click the Actions dropdown in the upper left corner and then select Preview.
Toggle between a Desktop and Mobile view of the email.
To exit the preview, click the "X" icon in the upper right corner.
Save a Template
As you are working on a campaign, you may want to save the template so that you can use the same branding and layout in future campaigns. Click the Actions dropdown in the upper left corner and click Save as Template.
This will download a file called “template.json” to your computer. You can rename this file so you can better find it in the future (make sure to leave the .json suffix on the filename).
When you create a new campaign, simply choose Upload saved template in the Template screen to load your template.
Another way to start a campaign with a customized template is to copy an older campaign. This will pre-populate the email template and design with the campaign you are copying.