There is one tool that i use quite a lot when i polish my shot, it is animation layer! Honestly, I have no in depth knowledge about it, but i thought i'd like to do a quick how-to tutorial about the tool. So here is the video:
I find this tool is very helpful and it kind of feels more organized. In my humble opinion, i think it could save us from destroying the previous animation that we've already had before we polish our shot. I mainly use it for adding small details such as breathing, head or hand shakes, staggers, and squash & stretch. I'm sure that it can be used to layer in a lot of other cool stuff as well! I hope the video is clear and i hope it helps. Please let me know if you had any trouble with the tool or if you had any questions about it, i will try my best to get back to you asap.
Thank you all for watching and Happy Animating!