Sometimes the small improvements can greatly help your productivity.
The Inline Preview plugin is a small improvement that can make your WordPress writing easier.
The basic Preview in WordPress opens up a new tab. The Inline Preview plugin shows you a preview directly where you're writing.
The Inline Preview plugin page is at http://wordpress.org/plugins/inline-preview/.
Install and activate it directly from your WordPress admin area.
When you write your post, everything will appear normal.
The Preview link will appear as normal, up in the top-right corner of the preview screen.
When you click the Preview Changes link, a sidebar will slide out from the right side of the screen
You'll be able to see a preview of your content, as in the image below:
This preview works for posts and pages. It also works with shortcodes and, in fact, anything you have inside your content.
Here's an inline preview for a WooCommerce shortcode.
Hopefully, Inline Plugin will make WordPress content editing a little quicker and less confusing for some users.