1. To submit a sitemap you need to have your Web Master Tools set up and verified, if you are unsure or haven't completed this then, follow these instructions.
2. Log in to your web master tools account
3. On the right click the sitemaps heading, you will get to the following screen and you have to click the ADD/TEST SITEMAP button
4. You will then see the following screen and all you need to do is add the word sitemap and click the blue SUBMIT SITEMAP button