The most common type of light switch is a one-way light switch, which simply turns a light fixture (or fixtures) on or off from one single location. Wiring two light fixtures to the switch requires "pig-tailing." Because electrical code dictates that one wire can only be attached to a switch's terminal screw, similar coloured wires are joined together with a wire nut, and from that nut a single wire runs to the terminal screw. This is done with the black and ground wires in the wall box.
Hold the switch box in position against the side of a wall stud. Hammer the two attached box nails into the side of the stud, using a hammer. Position the two light fixture boxes in the desired locations against the side of the ceiling joists, and hammer their nails into the joists. Push out one cable access cover in the back of both fixture boxes, and three access covers from the back of the switch box -- use a screwdriver.
Run 14/2 gauge electrical cable from the home's breaker box to the switch box, and one cable from the switch box to each of the fixture boxes. Push eight inches of the end of each cable through the cable access holes into the switch and fixture boxes (note that the switch box will have three cables entering it, and the fixture boxes will have one cable each). If necessary, drill 1/2-inch holes through the centre of wall studs and ceiling joists to run the cables, using a power drill and 1/2-inch wood drill bit.
Strip the first seven inches of outer sheathing from each cable in the switch box by running a utility knife blade along the centre of each cable's sheathing, and then cutting off the loose sheathing. Place all black and white cables, one at a time, into the correct gauge slot in the open jaws of a pair of wire strippers, 1/2-inch from the end of each wire. Close the wire-stripper handles and push it toward the end of each wire.
Hold all three bare white wire ends together, and screw on a wire nut. Cut one six-inch length of both black and ground wires using a tape measure and a pair of wire cutters. Strip off 1/2-inch of plastic coating from both ends of the six-inch black wire, using the wire strippers. Hold one end of the black six-inch wire to the two bare black wires coming from the light fixtures, and screw on a wire nut. Hold one end of the six-inch ground wire to the other ground wire ends, and screw on a wire nut.
Bend the remaining ends of the six-inch black and ground wires, as well as the black wire coming from the breaker box, into clockwise hook shapes -- use long nosed pliers. Attach the hooked end of the ground wire to the ground terminal screw on the side of the one-way switch. Attach the black wire from the breaker box to the outlet's bottom terminal screw, and the black hooked six-inch wire to the outlet's top terminal screw (the switch should be positioned with the "off" marking above the switch, and the "on" marking below the switch). Tighten the screws to hold the wires.
Push the wires into the switch box, and attach the switch to the box with the two small screws using the screwdriver. Position the faceplate against the front of the switch and attach it with the two screws.
Once the switch is installed, the two light fixtures can be installed, and the electrical cable installed in the breaker box. Once this is all carried out, turn on the circuit breaker serving the light circuit.