Polar alignment is still something that, every now and then, I can't quite get right, despite having been a visual observer for many years. I get it right first go 98% of the time. The other 2% is a fiddly mess.
On one occasion I forgot to ensure the clutches on the mount were tightened when I put the scope on prior to balancing. The mount rotated sharply and I was able to grab the scope just before it rotated around and crashed into the mount.
I don't have a list, but I have a set procedure I follow in setting up and in breaking down the scope and mount. I do things in the same order every time, and I don't move on to the next step until I"m sure the current one is finished and done with (and everything where it should be).