To use Section with outside DNS, simply go to your DNS hosting provider’s console and perform the steps necessary to add a new domain to Section. If you have not yet gone through the going live tutorial please visit it for a more in depth view of the entire process
Each registrar has its own method of adding CNAME records. Below are some links to instructions on adding DNS records for common hosts and DNS providers.
Amazon Route 53
DNS Made Easy
Having trouble? Contact your domain name provider directly for further assistance.