The solenoid has two large terminals on the top, and one or two smaller ones further down.
From the starter motor, a thick wire goes to one of the large terminals, and the other terminal is connected to the battery positive (+). When the ignition switch is turned on to start the machine, a wire becomes live, and this should be connected to one of the smaller terminals. The other small terminal should be connected to the machine frame, or earth.
So, connect up the small terminals first. You should hear a sharp click from the solenoid if all is well. If you get this far, then connect up the battery and starter motor large cables. The engine then should spin and start up. Tip - if you get any sparking from anywhere then somethings wrong. Also, you shouldn't feel any heat in any of the wires. If you do, disconnect the battery straight away.
John, May 2009