1 – Locate and open up your website’s robots.txt file

2 – Put your XML sitemap URL as shown in the sample below:

Sitemap: http://www.example.com/sitemap.xml

If You Have Multiple Sitemaps

If you have multiple sitemaps, you can either specify your sitemap index file URL as shown in the example below:

Sitemap: http://www.example.com/sitemap-index.xml

OR

You can specify individual URLs of your multiple sitemap files, as shown in the example below:

Sitemap: http://www.example.com/sitemap-one.xml
Sitemap: http://www.example.com/sitemap-two.xml