Some suggested steps:

1. Define it. When a client tells you they want articles, or they want blog posts, ask them to define what they mean. Are there interviews involved? How many? What’s the piece length?
2. Sway them. Sell them on the idea that what they want is considered an article by pro writers. It’ll instantly boost your rates. Make your case for why it’s an article gig.
3.  Sell articles. When you’re talking to clients who don’t quite know what they want, sell them on the idea that you should be writing an article for them, rather than a blog post, if they want their content marketing to be successful. Share the news of how Google is frowning on short keyword-driven posts.
4. Sell blog upgrades. If they want posts for an existing blog, sell them on the value of taking their blog to the next level, to more of a reported-story, magazine-type feel, and what that could do for their reputation and visibility.