I had a manager that asked me to put summaries at the top of my emails. It was super effective. I also label sections as to who they target (ex, when something

I had a manager that asked me to put summaries at the top of my emails. It was super effective. I also label sections as to who they target (ex, when something is a technical explanation that not everyone needs) and add footnotes (with raw data and the like) when it's appropriate. I'm a serial long-emailer, but I've learned how to interact with normal society ;)