Some building departments require metal or plastic conduit for all underground wiring, but most codes call for conduit only where the wiring is exposed or in a shallow trench. (Condensation can moisten wiring in watertight conduit. UF cable offers the only protection against water damage.)
Before you dig, have utilities mark underground lines. In the United States, call 811 to be connected to your local One Call center.
A square-bladed spade handles short runs. If you need to dig more than 50 feet of trench, rent a powered trench digger.
Check local building codes. Some allow a shallower trench if the cable or conduit is covered with a 2X6 pressure-treated plank.
Once power is brought outside, about 8 to 12 hours to dig trenches, run 60 feet of cable, and install several lights
Shovel, posthole digger, hammer, drill, fish tape, pliers, garden hose or sledgehammer
Laying out and digging trenches, fishing cable through conduit
Install a receptacle or LB fitting, bringing power to the outside, and check that the new service does not overload the circuit. Call the utility company to mark lines.
Conduit and fittings, conduit clamps, stakes, string line