How do you remove the guard ring on the controller

Unfortunetly, you don't.

They contain sensors that send data to the headset about where it is so if you take off the rings the controllers wouldn't work.

If you want ringless buy the pro controllers but they cost $300 USD so personally I would just deal with the rings

But you could technically a hand saw would work just fine to cut through the plastic but remove the batteries first or risk electrocution!