Wood panelling is typically applied directly over the drywall of your interior walls. To install electrical sockets, you will need to cut through both the panelling and the drywall to create an access hole for setting your junction box into. This is best accomplished through the use of "old work" junction boxes, which are specifically designed for retrofitting, or remodelling projects in buildings that have already been framed and finished. These boxes make the work simpler, since they are mounted between studs, anchoring directly to the panelling or drywall itself. Have your electrician make the connection at the main panel for your electric wiring, to ensure code compliance.
Locate the breaker to the wire you will be connecting to your junction box. Turn it off, if it is not already.
Depress the buttons on both sides of the electronic stud finder to activate it. Drag it over the surface of the wall, marking with chalk every place the finder beeps and lights up to indicate the presence of a wall stud. Choose a spot between two studs, at least 12 inches up from the floor.
Position the paper template that came with your junction box on the panelling and trace its outline onto the face of the wall with the chalk. Drill a hole in one corner of this outline with a 1/2-inch spade bit. Slip a fine-tooth blade on a jigsaw into the hole. Cut the hole for your junction box following the outline you marked on the panelling.
Drill a hole through the top plate of the wall directly over the hole you just cut, and feed the end of the wire your electrician connected at the main panel down through the wall. Insert a wire fish tape into the hole you cut in the panel and use it to drag the wire out of the hole. Punch out the top hole on your old work junction box and feed the wire through the hole.
Press the junction box into the hole in the wall. Tighten the screws in the top and bottom of the junction box so the clamping mechanism grips the edge of the panelling and drywall to anchor it in place.
Remove the wire nuts from the end of the wires. Wrap the black wire around the top screw on your outlet and tighten it with a screwdriver. Do the same with the white wire on the bottom screw and the green wire on the green screw. Tuck the wires back into the wall.
Fit the outlet into the junction box and install the mounting screws. Tighten the screws and fit an outlet cover over the front of the box. Install the mounting screw in the centre of the plate and tighten it. Restore the power at the breaker box.