This plugin will improve SEO by helping search enginess better index your site using sitemaps.
Use this plugin to greatly improve SEO to create special XML sitemaps which will help search engines like Google, Bing, Yahoo and Ask.com to better index your site.
With such a sitemap, it's much easier for the crawlers to see the complete structure of your site and retrieve it more efficiently. The plugin supports all kinds of WordPress generated pages as well as custom URLs. Additionally it notifies all major search engines every time you create a post about the new content.
Step 1: Install it
Install this plugin by navigating Plugins -> Add New within your Admin dashboard, then searching for ' XML Sitemaps ', then click Install, then activate.
Alternatively you can head over here, download the plugin and then upload and extract it to your WordPress plugins folder.
Step 2: Use it
Use the plugin as shown in the below screenshots:
Reference
Read more here.