At the other end you put a momentary switch. To start the laptop using the scheme mentioned, all that has to happen is for the two wires to be in momentary contact - essentially the same as you momentarily pressing the power on button. I have a laptop in the back of my car, ran phone up front to a small momentary push button...works like a charm. I set the bios (I have a Dell) to go into hibernation when the power button is pressed. When from an OFF state I press the button and power on. From an on state, a short press sends it into hibernation, a 4-second press shuts the machine down.