For HTTPS you’ll need to purchase a SSL certificate for your domain.
Update: JerseyConnect now offers free domain-validated certificates for websites hosted with us. See this post for more information!
The vendor issuing your certificate will need a CSR (certificate signing request) generated from our web server. You can generate a CSR in the cPanel interface or you can contact JerseyConnect and request a CSR be generated for you.
Certificates also have different levels of validation. This article explains the 3 types of certificates along with some other basic information regarding SSL certificates, https://www.verisign.com/en_US/domain-names/web-presence/website-optimization/ssl-certificates/index.xhtml.