This is basically the same thing as usual but with the new structure.
If you have modified a little the stock android (hosts file, root, kernel, etc.), you may experience a fail in OTA update;
If you have a bootloop/soft brick/not sure of the state of your android system;
This is the solution.
This WILL NOT delete your data and apps. This will remove your custom kernel/root/hosts/recovery through (which is a good thing because it will be clean then).
I assume you already have anything to do fastboot command. If not, see this good thread.
1) Download your system image for Marlin (Pixel XL) on google website.
For November update, there are 3 versions:
NDE63V US, except Verizon
2) Unzip the file marlin-nde63v-factory-a66866ba.zip
3) Unzip inside the new directory (marlin-nde63v) the image-marlin-nde63v.zip
4) Reboot into bootloader
adb reboot bootloader
fastboot flash bootloader bootloader-marlin-*.img fastboot reboot-bootloader fastboot flash radio radio-marlin-*.img fastboot reboot-bootloader fastboot flash boot_a boot.img fastboot flash boot_b boot.img fastboot flash system system.img fastboot flash system_b system_other.img fastboot flash vendor vendor.img fastboot flash modem modem.img fastboot reboot
6) To add TWRP and Root:
fastboot boot /path/to/twrp.img
Reboot into the installed recovery
In TWRP, install supersu.zip
Root thread for more information.
TWRP thread for more information.