Micah Lee did a talk about how he does it. In essence he uses Tor to connect to the VPN. He also explains how to pay for the VPN anonymously.
I think it was part of his Qubes OS talk: https://youtu.be/f4U8YbXKwog
I think it was part of his Qubes OS talk: https://youtu.be/f4U8YbXKwog
If your traffic is interesting enough, the money trail will eventually lead back to you.