Installing Active Directory as a domain controller:
Install Windows Server 2012
Computer management > update server administrator
Server manager > Local Server > update server name
Server Manager > Manage > Add Roles and Features > Next > Next > Next >
Select: Active Directory Domain Services and DNS Server
Accept each with "Add Features"
Next > Next > Next > Next > Install
Now, Promote this server to a domain controller
add a new forest, {enter domain} > Next
Leave defaults and enter a DSRM password(Store this in a safe place)
Next
Select Credentials to Delegate (enter your user/pass)
Next > Next > Next > Next > Install
Active Directory on Windows Server 2012 is complete.