Here is the strange part: with debit card. Theoretically the government can identify and arrest all VPN providers in 24 hours. For some reason they have never made a single VPN-related arrest as far as I know. This has led many (including me) believe that VPNs are government honeypots. People are going to circumvent censorship one way or the other. If they provide VPN for those who are really seeking it, they will lose their power for censorship but not surveillance. I assume they don't care so much about people watching porn as they care about citizen journalists writing for BBC (many of whom have been arrested).
Many VPN providers these days accept Bitcoin, just buy it locally and send it around a little and you're good to go. Though I doubt the government cares enough to look into everyone who buys VPN via other means anyways.