https://ipv6.he.net/
Paste the following into /etc/network/interfaces
auto he-ipv6
iface he-ipv6 inet6 v4tunnel
        address 2001:470:66:1cd::2
        netmask 64
        endpoint 64.62.134.130
        local 23.234.251.249
        ttl 255
        gateway 2001:470:66:1cd::1


$sudo /etc/init.d/networking restart

2001:470:66:1cd::2