
People will despise me for it but I’ll just come out and say it. What saved my writing from being a pompous Germanic mess was the good old Strunk and White. It’s fashionable to hate on Strunk and White but I read that tiny volume twice and now I’m the author of the very moderately Germanic posts you all enjoy.
Strunk and White give examples of sentences, and for every single one I’d exclaim, “Yes! That sounds beautiful!” And then Strunk and White would explain why it’s a horrid, ugly sentence.
Just to give an example (which Strunk and White would tell me to reduce to “Example:” but then nobody is perfect):

I was totally the “he is a man who” (or even worse, “I’m a person who”) type of writer. But I’m mostly cured. OK, partially cured.
Strunk and White have become less popular because their rules hurt the feelings of the wordy. Or the grammatically challenged. But they are great.
To practice, I recommend writing a 500-word piece on any subject. The last movie you watched, your favorite podcast. And then try to edit it down for maximum clarity.
Another great exercise is to summarize in one sentence an episode of a TV series or a book you read. Write the sentence in Word and see what the grammar check flags as possible problems. Do that at least once daily.
In short, clarity, brevity, and a lot of practice.

