I recently have 3 domains, contouso.com, one.contouso.com, and two.contouso.com. The thing is, they were created separately and all are parent domains. How do I join the two other domains so that they will become child domains of the contouso.com. All three domains already have existing clients and services running independely from the other, but they are conected thru trust relationship, non-transitive, external.

Also, if you have the best way on how to change a domain name, say, from one.contouso.com to go.contouso.com without negative effects.