2002 Toyota Sienna sensor

I had autozone test the car due to a check engine light. The trouble code was P1135 for a bank 1 sensor 1 sensor. From a lot of research, I know that it is on the exhaust manifold close to the firewall. What is the best way to replace the sensor:

Do I need to spray WD-40 on the existing sensor?
Do I replace while the exhaust manifold is hot or cold?
Do I need a special wrench?
Do I try to replace from above or below mini-van? I prefer from above due to lifting limitations.
Do I need to put anti-seize compound on new sensor?

Thanks,
Rob