This diagram illustrates the wiring for a circuit with gfci receptacles followed by a light and switch. By connecting the switch to the load terminals on the gfci, the light is protected against ground faults as well.
The black wire is splice to the output on the speed controller and to the black, fan wire at the other end. The red wire is spliced to the output on the dimmer and to the blue, light wire at the other end. The neutral from the source is spliced in the switch box with the white wire, and to the neutral wire on the ceiling fixture at the other end.
Here the exhaust fan is controlled by a timer instead of a switch. There should be two hot wires and a ground coming out of the timer casing, splice one of these to the hot source. Spice the second to the black, cable wire running to the fan. Splice the source neutral to the white cable wire and the ground to the ground wires. At the fan splice the wires, matching the colors of each.
The black cable wire is connected to the top terminal on the switch and spliced to the black and blue wires at the fan at the other end. The neutral source and ground are spliced through to the white and ground connections at the fan.