How to configure a wireless router connected to a network hub?

Our office has a wired network that provides internet through a gateway PC. We bought a wireless router and had it connected upstairs to one remaining cable of the wired network to WAN connector of the router. The idea is to provide access point for laptop users upstairs (all ports on network are filled). How do I configure the router to provide internet access to wifi devices? The wired network is configured with this static gateway ip: 192.168.0.1