You can preview website in Helm by adding a domain alias based on your domain name and the server host name (or any resolved domain)

For example, you want to preview mydomain.com on a server with host name sv3.myserver.com

Please log in Helm, browse to domain control panel page, choose Domain Aliases option, add a domain alias mydomain.sv3.myserver.com

You can now view your website via mydomain.sv3.myserver.com

Alternatively you can add domain alias for mydomain.other-resolved-domain.com