How do I downgrade from Lollipop?

So I remember my excitement when I saw that my beloved Tegra Note 7 showed me that the 5.1 OTA is available. Needless to say, the excitement died down after a week or so of using the tablet. The problem that bothers me the most is battery drain. In just about 10 hours in standby mode with WiFi off, my battery reduced 13%. I take it off the charger at 100%, WiFi on, in standby mode and viola, in 10 minutes, 3-4% battery drain with no activity at all. Now I hardly get more than 2-3 hours of activity out of it but when I was using Kitkat, oh boy. 2 days in standby with WiFi off and 1-2% battery loss.....Amazing. Also, I miss the power control so much <3 (I really don't think the Activity Launcher way to get the SHIELD Power Control Menu works at all)

Now I really want to downgrade it to Kitkat but have absolutely no clue how to do so. I'm not rooted currently and I've tried searching in the forum for existing topics for but couldn't find any. It'd be great if someone wrote a 'For Dummies' guide as to how to downgrade from Lollipop on an unrooted device in the simplest way possible.