There are several methods. [1] The most aggressive method-02 and method-03 on my document will block VPS and some data-centers but that also means it will block some legit users that are on a VPN. Most VPNs transit a data-center. If experimenting with these methods use a test server that you do not care about and set up a dummy site and ask people in your circle of friends to test it. I have to step away for a bit but if you have questions I will try to answer.
[1] - https://nochan.net/b/Internet-Crap/20260606-How-To-Block-Som...