To connect up the subnets to a single router, you will need a business-class router that can handle multiple LAN zones. Most basic routers are only for a single network range, but you can find many firewalls and more expensive routers that can manage multiple networks. For instance, on the Sonicwall TZ 100 series firewall and greater, you can configure each physical ethernet port to an independent network, which can each be the default gateway for a subnet.
If you're wanting to have six subnets, you'd need to look into a Sonicwall TZ 215 or NSA 220 firewall to have the number of ports needed for that many subnets.