It's just a parallel circuit. For instance, if your power cord has a black wire and a white wire, as does each light, you wire the power cord black to every black light wire, and the power cord white to every white light wire.

wall power------black---------light 1 black-----light 2 black-----etc
wall power------white---------light 1 white-----light 3 white-----etc

Does that make sense? Just look up a diagram for a parallel circuit for more information.

And a PRECAUTION!!! Make sure that the total draw of your lights (when combined) does not exceed the capacity of the power cord you wire them together with... or you might burn house down Basically, make sure you buy a heavy-duty, 3-prong (with ground) power cord to wire to all of your lights.