One that goes through all three branches of government, the way it's been since we decided "no taxation without representation" is how such things should be collectively implemented.

If a citizen's stance is there is no such thing as a legitimate tax, perhaps there should be a legal process for banishing them from all public services, including roads, electricity, telephone, fire and rescue services, etc. and make consuming them a crime. But I guess even that would be a problem because we need to pay for the justice system that would prosecute such a sovereign citizen that breaks the rules...

Basically an "opt-out" of modern life almost in its entirety. I think most people that subscribe to "no legitimate taxes" might be surprised how isolating that would be if they actually think it through.

To be clear, I don't think this is a good idea, it's simply a thought exercise.