How do I change a swith to a switch/outlet combo?

My current set up has a single switch tied to a single light. The electrical box has two black wires, both connected to the current switch, two white wires, both tied together, and ground. The combo switch/outlet has a green screw and silver screw on one side and a brass screw and two black screws, connected via a break-off tab, on the other. I would like to have the outlet work independently from the switch.How do I change a swith to a switch/outlet combo?Texas is also correct.How do I change a swith to a switch/outlet combo?Easy, hook the whites to the silver screw, put the hot lead on the outlet terminal, put the light lead on the switch terminal. There should be a diagram on the box that the unit was in. If you still have trouble, call a qualified professional electrician.How do I change a swith to a switch/outlet combo?Jim is correct.