>>33506365 (OP)
English teacher here.
Know that content and expression are two separate things that use different parts of your brain. A lot of trouble comes from trying to fo them at the same time.
So get clear in your mind WHAT you want to say before you even begin to think about HOW to say it. Condense your point down to a single simple declarative sentence. Write it down. THAT is the message you want to deliver.
THEN think about how to say it. And here the key is to imagine yourself actually SAYING it out loud. If you were going to speak this, what would you say first, then what, then what?
The point here is that we all have far more experience talking than writing, and we will almost always instinctively say it in the clearest and most logical way. But too many people somehow get it in their heads that writing-logic has to be different from talking-logic. It doesn't.
And finally, say it in the most natural way to you. That probably means simple language, not high-falutin fancy words. It is better to be clear than impressive.