When you say WiFi, are you talking about the 802.11 standard? If so you're gonna need some hightech stuff, or use a actual computer for your robot. I'd go with what the Admin said, just pick one of the wireless transceivers he recommended. Most of the ones out there use UART which is really easy to learn. My personal favorite is the XBee. Then you can either use some variation of Hyperterminal or look up how to program using the come port.