cool remove radiator cap. Start engine and let idle -- just like the other post said -- set heater inside temp to 90 degrees. Once engine has warmed a bit gently squeeze the upper radiator hose. This forces air bubbles into the radiator and up thru the filler hole.
I always worry about removing the radiator bleed hole screw since my radiator is still original. Not looking to cause leaks, cracks or other issues there.