An article is the bread-and-butter of a journalist's or freelance writer's portfolio. By definition a non-fiction work, this type of writing allows for a minimum of creative writing quirks. To be successful, an article must communicate new, and factual, information in an interesting way.
Outline your article.
Write the article.
Check your facts.
Proofread. Even the best, most clever article is nothing if it's filled with spelling and grammatical errors. Make sure to read over your article before you send or submit it. Better yet, have a friend or spouse read through it.