Here a gfci receptacle is added at the end of a row of duplex receptacles for single-location protection. The first outlet is connected to the source and 2-wire cable runs from box to box. All wires are spliced with a pigtail at the devices to pass current from one to the next. The load terminals on the gfci are not used and it does not protect the other receptacles in the circuit.
In this diagram, two receptacle outlets are wired in the same box with a separate 120 volt source feeding each. Three-wire cable runs into the box. The black and red wires are hot and each is connected to one of the receptacles. The white, neutral wire is splice to each outlet so they share the return path. This is appropriate for standard duplex receptacles, but should not be used for GFCI receptacles. GFCI’s must have dedicated neutral connections to work properly.
This diagram shows the wiring for multiple receptacles in an arrangement that connects each individually to the source. All wires are spliced to a pigtail which is connected to each device. This wiring allows for voltage at each device independent of the other outlets in the circuit.
The hot source is spliced to the black, fan wire and the black wire running to the dimmer. At the other end, the black cable wire is spliced to one of the hot dimmer wires, it doesn’t matter which one. The other dimmer wire is spliced to the red wire in the switch box which is spliced to the blue, light wire at the other end.