I added NS (Name Server) records to the DNS for my domain under the Manage Domains option. I added ns1.MYDOMAIN.com, ns2, and ns3. For their Values, I put in ns1.dreamhost.com, ns2, and ns3. For confirmation, it asked for the IP addresses:
ns1 = 126.96.36.199
ns2 = 188.8.131.52
ns3 = 184.108.40.206
And then I updated the WHOIS info for my domain under Registrations with the new nameservers.