1. Use a router and run dd-wrt on it, then on your computer you connect to another vpn server, now you're doing VPN over VPN, a multihop.
2. This link shows how to do VPN over Tor;
https://www.bolehvpn.net/forum/index.php?topic=6933.0 If as example, you also ran openvpn off a router, then you would end up in this tutorial as; VPN Tor VPN
3. Use virtualbox and install a system into it. Connect to the VPN on your Host, then start Virtualbox and run your Guest system and connect to the VPN on it, and now you are doing VPN over VPN, a multihop.
By the way Virtualbox uses 'NAT' as the default network adapter setting and to do this in Virtualbox you need to change that and set it on;
Bridged Adapter.