2000 Honda Civic oxygen sensor

First of all you need to know which of the two O2 sensors needs to be replaced. After that you need to purchase a new sensor and Do Not get a universal sensor. Get a direct replacement. I cut the wires off of the old one and slip deep socket over it and remove the old one. There is a special socket/wrench for this. The new one I tighten with an open end wrench. Route the wires to the connection and you are set. You need to reset the computer codes and you should be off and running.

Good luck