Go to your registrar's website and set the nameservers for your domain to:
ns1.geoscaling.com
ns2.geoscaling.com
ns3.geoscaling.com
ns4.geoscaling.com
ns5.geoscaling.com
Before or after you do this, add the domains in your GeoScaling account and add some records.
It can take up to 48 hours (usually much less) until GeoScaling takes control of your domain after you changed the nameservers, so please be patient.