(OPTIONAL) If you do not have a DHCP server, you need to supply additional network information on the command line. Also append ip=x.x.x.x netmask=x.x.x.x gateway=x.x.x.x. Use the same addresses you supplied when generating the kickstart script.
Wait for the automated install to complete. With Red Hat 6 you may need to choose a NIC to use and/or confirm that the disks will be completely erased.