How do I know what wires go on what side of the solenord switch

Check voltage at starter relay. That line with arrowhead, at the relay, load side. Voltage at that terminal is hot all the time, when the relay is energized, that line with the arrowhead moves to the other terminal, voltage goes to starter motor. Voltage for the control/coil side of relay, comes from the ignition switch/crank position through the neutral or clutch switch, depending on tranny, to coil side of relay.

Any testing, make sure the tranny is in park or neutral and a functional e-brake is set.