Site %1 has been created. To finish configuration of %1: Ensure that %1 is linked to other sites with site links as appropriate. ...

Site %1 has been created. To finish configuration of %1:  Ensure that %1 is linked to other sites with site links as appropriate.  Add subnets for %1 to the Subnets container.  Install one or more Domain Controllers in %1, or move existing DCs into the site.   You will not see this message again until the next time you start Active Directory Sites and Services.