I just bought another domain.
How would I transfer directories of my sub-domains to my new domains?
For example, sub.domain.com, how can i transfer it to sub.newdomain.com?
Shell access is the best way.http://wiki.dreamhost.com/Shell
If you've got time and want an easier way, you can treat it as a backup and restore:http://wiki.dreamhost.com/Backup_Website_Manually
EDIT: Even easier, if it's the same user, create sub.newdomain.com and this will make a new folder in your home directory. Now rename it sub.newdomain.old and rename sub.olddomain.com to sub.newdomain.com