PTO is started and stopped from the tractor’s controls so the operator can run a machine while staying in the cab. Tractors have pedals, levers, and buttons for driving and using tools. You often find a clutch or an inching pedal to change speed slowly, brake pedals that can be used separately for left and right wheels, and a hand throttle to hold the engine at a steady speed.
Modern tractors may add power-shift gears or CVT so you change speed without stopping. There are also switches for the hydraulic lift, buttons for the differential lock (to help when one wheel slips), and dashboard displays that show speed, engine temperature, and warnings.