WordPress has some great built in features to create a sitemap, and automatically update and submit it. Using sitemaps has many benefits, not only easier navigation and better visibility by search engines. Sitemaps offer the opportunity to inform search engines immediately about any changes on your site. One single page you show the structure of your site, its sections, the links between them, etc. Sitemaps make navigating your site easier and having an updated sitemap on your site is good both for your users and for search engines.

Best Plug-in for WordPress Sitemap:

To Create sitemap you can use WordPress SEO Plugin . It has the most advanced XML Sitemaps functionality in any WordPress plugin. Once you check the box, it automatically creates XML sitemaps and notifies Google & Bing of the sitemaps existence. These XML sitemaps include the images in your posts & pages too, so that your images may be found better in the search engines too.

How to configure WordPress SEO Plugin:
To configure the plugin, go to Dashboard > SEO > XML Sitemaps, and check the box Scroll down and click “Save XML Sitemaps Settings”. Actually, this file contains links to other sitemap files that contain the website links. If you use this method, your sitemap will be at:

http://yourwebsite.com/sitemap_index.xml

There are other settings, to help you select which content is to be included, but unless you have a very large website its best to include everything in your sitemap, and use robots.txt to control what is indexed by search engines.

How to update automaically:

Step 1: Remember to make a note of the address of your sitemap, for example:

http://yourwebsite.com/sitemap_index.xml

Step 2: Now we can create a custom sitemap submission URL for each of Google, Bing, Yahoo and Ask. Now open a plain text editor. Copy and paste the following lines into it, exactly as shown. Each URL must be on a separate line.

<script src="http://pastebin.com/embed_js.php?i=wdrsA3MW"></script>

You can test these by doing a ping manually. Copy each of your customised URLs, one at a time, into your browser address bar and press enter. If it works you’ll get a message like “Thanks for submitting a sitemap”.
To automate this process we add these URLs to the “Update Services” settings in WordPress.

Step 3:
a) Go to the wordpress Dashboard > Settings > Writing. Scroll down to “Remote Publishing” and click the check box of “XML-RPC”.
b) On the same page locate “Update Services” and copy the custom sitemap submission URLs and paste them into the box underneath “Update Services”
c) Then click “Save Changes”.

It’s done, hope this tutorial let you create WordPress Sitemap and update it automatically.