Some of our visitors have reported that they lost their blog traffic after adding this sitemap so try this on your own risk. We are not responsible for any loss if something goes wrong.
An XML, also called Google sitemap, is necessary for a blog or website which helps search engine crawlers to crawl and index content on your blog easily. Blogger blogs with .blogspot sub-domains contain an xml sitemap on them which is generated automatically and kept updated with your latest content. The sitemap of blogs with .blogspot sub-domain can be accessed at http://yourblog.blogspot.com/sitemap.xml and you can submit it directly to Google Webmaster Tools or anywhere else, but when you add your custom domain to your Blogger blog, the xml sitemap couldn’t be accessed anymore and thus you need to manually configure XML/Google sitemap for your Blogger blog. To do so, follow below simple steps:
You are all done! Now whenever Google will crawl your blog, it will first look robots.txt file on your blog as it always do and then will crawl your entire blog. This XML sitemap doesn’t need to be submitted in Google Webmaster Tools also and you don’t need to update it after you generate and add it to your blog. All latest posts are fetched via atom.xml on your blog and your latest content is automatically suggested to Google bot. Thus your blog content will get indexed easily. Enjoy!
Additional: You can also use this free XML Sitemap Generator for sitemap generation.