Before activating your email campaign, make sure your email message is fully composed and that you’ve applied the appropriate filters to target the right customers. Once everything is in place, go to the top of the page and click the Finalize and Activate button in the top right corner to turn your campaign on.
To change how many customers receive your campaign, update the basic and additional filters associated with that email campaign. For more on email campaign filters see Email Campaign Basic and Additional Filters
For more on the email campaign that are available see Email Campaign Templates