After you have a plan in place that defines your sites, IP subnets, site links, costs, and bridgeheads, you can proceed to create the objects in Active Directory. Here is the general course of action:
Rename the Default-First-Site-Name object
Create new Site objects
Create Subnet objects
Create Site Link objects
Designate bridgehead servers
After completing this work, the KCC should handle any changes you make to the distribution of domain controllers and Global Catalog servers in the network with no further intervention.
The name for the first site is a little long and clumsy for most uses. The steps to rename it are listed in Procedure 7.4.
Procedure 7.4 Renaming the Default-First-Site-Name ...