What should one switchman do first when placing a portable hand trolley to a car?

When placing a portable hand trolley to a car, the most important step is to first put one end on the contact shoe. This action ensures that the trolley is properly connected to the car's electrical system, which is essential for safety and functionality. The contact shoe is designed to make an electrical connection that allows the trolley to operate effectively, which is critical for performing tasks such as shunting or moving the car.

By focusing on this step initially, the switchman can ensure that the trolley is prepared for use before addressing other aspects, such as alignment with the track or securing the trolley with safety chains. This prioritization helps minimize the risk of accidents or equipment malfunction during operations, aligning with proper safety protocols in train handling.