Coolant flush procedure

[sub truck]

I have 2000 suburban. I'm planning a radiator flush. Where is the radiator cap? I see the cap on the overflown tank is rated at 15 psi. Do I put water in the Overflow tank to flush the radiator? Do I pour the coolant in the overflow tank to filll the radiator? But how will the water or coolant be drawn into the radiator? Do I need to start the car? Will the engine overheat while the water or coolant is being drawn into the radiator? This design is new to me. I'm just wondering what the procedure is flushing this system.

Thanks

[ChevyTech007]

The cap on the overflow jug is the radiator cap. You can drain it like normal. Then fill it through the overflow jug. I will flow into the radiator. Do not fill it up all the way. Leave about 3 inches for expansion.