Although software solutions exist, by far the simplest way is to buy a WiFi router which can be be had for less than $20 if you shop around. The only configuration required may be to clone the MAC address of your PC's Ethernet port in the router to allow the router to connect via your broadband connection. Many routers have an option to clone the MAC address for you. Just plug the modem into the WAN port of the router and your PC into one of the 4 available LAN ports. Then cold start modem, router and PC and all will work. Any WiFi device can connect to your router just as it would at Starbucks, McDonalds or wherever open WiFi connections are offered.