It's hard to get started when you aren't 100% clear on what you're writing. And once you get started, it's hard to keep going if you have to keep rethinking what you're writing. So, do all of the hard-thinking up front.
Write a one sentence description of what the article is about. Then restate it in different words. Then restate it again and again until you have a one sentence description that is jusssssst right ...
Be like goldilocks.
If you need to restate it 12 times - - do it. You'll find it much easier for the article to flow. Because now you know where it's going. Simply write what proves that one sentence. And trim out anything that doesn't fit it.
This has helped me in my experience. What's worked for you?
Have a great day!