Best way to document everything at work to protect yourself from crazy boss

So I am dealing with a crazy micromanager boss who has personal issues. I want to protect myself as much as I can I want to fight back and play his game in a very smart way. His abusive behavior is usually done orally in our one on one meetings. I want to keep tabs on everything but I'm not used to documenting… what are your best advices in keeping tabs at work in a written and professional diplomatic way?