HTTPS is set up just like an HTTP connection. It is set up as a Web Service.
Steps to setup.
1. Setup the Web Service Connection in the "Web Service Connections" page. Setup the type, url and other required parameters. If it is a Client Authenticated then you can check the "Client Auth" checkbox. You will need a private key with a matching certificate to use this option.
2. On the destination node choose Web Service and fill in what you are going to send. Just like Database Connections the URL and connection related items are defined in the Web Service Connections page.