Connecting two electrical wires outside is quite easy, though you must follow proper safety guidelines. It is for this very reason that many people choose to hire an electrician rather than handle electrical repairs on their own. By following strict safety procedures, however, you can perform simple electrical repairs yourself. The procedure for connecting two wires is the same for both solid copper and stranded copper wire types.
Locate the two wires you wish to connect.
Determine which of the wires is connected to the power source, then turn the power source off and completely remove the wire from the power source. If the power source is a breaker box, locate the breaker for the circuit you are working on, turn the breaker off, remove the breaker box panel cover with a Phillips head screwdriver, then remove the wire from its circuit with a flat head screwdriver. This ensures that, even if someone accidentally flips the circuit breaker on while you are connecting the wires, you will be safe because the circuit is physically separated.
Trim 1 1/2 inches of insulation from the ends of each wire using wire strippers.
Align the wires side by side with the bare ends facing up.
Twist the wires together using lineman's pliers. Simply hold the two wires in one hand, apply the pliers to the ends of the wires, and twist around slowly in one direction two or three times until they are secured together. If the ends of the two wires are uneven, cut them to be even with one another using the cutting edge of the lineman's pliers.
Twist the wire connector on clockwise, using your fingers, until it is fully secure. Make sure the wire nut fully covers the bare wire.
Lightly bend and tug the wires just enough to be sure that the wires are firmly connected.
Wrap the connection in black electrical tape.