You'll need to have a system running that is accessible through a DNS record. It should have access to the public Habitat depot, https://app.habitat.sh so it can download the required packages.
You'll need to register an OAuth application for GitHub. You need the client ID and client secret that are created for the application later in this guide. Your system needs to have access to https://github.com so that it can authenticate.
Your system also needs to have an FQDN that can be resolved, for example depot.example.com. This will be used in your OAuth application's "Authorization Callback URL." For this example, use http://depot.example.com/#/sign-in. The /#/sign-in is required.