PVC conduit is the preferred method of installing underground electrical wiring. When properly assembled, PVC conduit is waterproof and will not corrode or decay. PVC conduit is also much easier to work with than metal conduit and requires few tools to assemble.
Use the hammer to drive the stakes into the ground at the beginning and end of where the conduit will be installed. If the conduit is not being installed in a straight line, also drive in stakes at any points where the conduit will change directions. Tie a piece of the string between the stakes to outline the path of the conduit.
Use the shovel to dig a trench that is 45 cm (18 inches) deep along the path of the string. The trench will need to be wide enough to allow easy access to the conduit when it is being installed. Typically a 30 cm (12 inch) wide trench will provide adequate space for the conduit assembly.
Measure the length of the trench to determine the length of PVC conduit that is required. If the length of the trench is longer than the sections of PVC conduit it will be necessary to join one or more sections of conduit with PVC unions. To join the PVC conduit using the PVC unions, coat the inside of the union and the outside of the end of each section of the PVC pipe with the PVC primer. Allow the primer to dry for at least one minute. Once the primer is dry, coat the end of each section of the PVC pipe with the PVC pipe cement and insert the pipe ends into the union. Hold the pipe ends securely in the union for at least a minute while the pipe cement dries and secures the two pieces of the PVC conduit together.
Cut the final section of the PVC conduit using the PVC pipe cutter so that the assembled sections of conduit and unions complete a continuous section of conduit for the length of the trench. Insert the wire into the conduit and work the wire down the length of the conduit until there is about a metre (several feet) of wire extending from the far end of the conduit.
Place the conduit in the bottom of the trench. Refill the trench so that the conduit has 45 cm (18 inches) of soil cover for the full length of the conduit.
Before refilling the trench with dirt it is always best to insert the wire in the conduit. If there are any issues getting the wire through the conduit it is best to resolve those before the conduit has been buried in the trench.
Make sure to follow all local codes and permitting requirements for any electrical installation.