Directing the search engines to your sitemap is easy.
1.) Locate your sitemap (most likely
https://yourdomainhere.com/sitemap.xml)
2.) Open your robots.txt file on your web server via FTP. (the
WP File Manager plugin can be used if you're on WordPress)
3.) Add "Sitemap: " followed by the location of your sitemap on a new line below any other text and save.
e.g.
Sitemap: http://yourdomainhere.com/sitemap.xml