How do you burp the cooling system on a 2000 Chevy s-10?

Leave the radiator cap off, cover the grille with cardboard. Start the engine, turn the heater on high. Tach the engine to 2000 RPMs and hold it there. Let it run like that until it gets hot enough for the thermostat to open up. Personally, I just use a vacuum refiller when doing coolant flushes, but they are very expensive.