If you are ready to start flashing stuff on your shiny new Nexus 6 you'll be happy to know that developer "DeesTroy" and the TWRP team have released Team Win Recovery Project for the Nexus 6! Installing it is super easy. If you are already rooted you can just download the image and flash it with an app like "Flashify". If you aren't rooted you will need to boot your phone into bootloader mode, drop the recovery image in your folder containing your fastboot and adb files, then open a command prompt from within that folder and type "fastboot flash recovery "nameofrecovery". Next just scroll over to recovery boot option from the bootloader menu using volume up or down and press power to select. This is fully working and the first thing I would recommend you do is create a full nandroid backup. This way you can always get back to stock easily if you mess something up. Head to the link below for the download.
Via XDA