flushing on 1992 Chevrolet 1500 Pickup

can someone please tell me how to flush the radiator?

Asked by for the 1992 Chevrolet 1500 Pickup
At the part store they sell a "radiator flush" you just add it to your radiator, let the car idle for 10 min, then drain and fill. Read the bottle for more instruction. the bottle cost $5.99-8.99 it is available at Autozone, Pep Boys, NAPA, and Carquest. To have the job done at the shop would cost $65