After your AdSense account has been activated, you can start showing ads on additional sites. You can show ads on any site that you own that complies with AdSense Program policies. To show ads on a new site, first add the site to your sites list in AdSense.
Changing your existing site
If you want to change the site where you currently show ads, make sure you add the new site to your sites list first before you place your ad code.