Once you have created a free website through Google, you will want to have Google automatically generate a sitemap for you. This article will tell you how. I would suggest that you bookmark this article and print yourself a copy when you have finished building your site and are ready to submit your site URL to Google.
You will first need a Google e-mail account, if you do not already have one. It's easy, and free. Once you have a Google e-mail account, go to your Google Webmaster Tools account.
On the Webmaster Tools Home page, click Verify this site next to the site you want, if you have more than one site.