Navigate to the page on which your article appears. If you have permission to edit the article (generally only articles that you wrote), you should see the following over the article:
Click on the pencil and paper icon at the end of the bar. This will open your article in an editing mode. Make any changes and hit save. You do not need to change any of the lower options (category, meta tags, etc.)
Once the article is saved, your update is submitted for publication, and not appear immediately. If you do not see your changes within the next business day, contact Information Services.