And be sure to let the thermostat open before you finish the job. The radiator will appear full and flowing until the thermostat opens.
Do what JBFP says then fill the radiator and reservoir. Let it run with the radiator cap off until the engine warms up. You'll see the fluid level drop when the thermostat opens. At that point top up both the radiator and tank and watch a few minutes more to make sure the air is all purged.

90 LWB - Not your average bear

"You are what you are, and you ain't what you ain't." - John Prine