The way I do it, I first drain the radiator, dispose of correctly, then set the heater to high, then I disconnect the radiator top hose and rig up a way to catch the water from it into a big tub or garbage can. Next I start & idle the engine while I run the garden hose into the top of the radiator just enough to keep it filled. After a few minutes water will start to pour from the top hose into the tub. Watch carefully, as when this occurs you’ll have to add more water to keep the radiator full. After a while what comes out of the top hose will be clear, looks like water, stop the engine and let it cool off completely. Might take 4 or 5 hours. Then drain the radiator again, and refill with 100% coolant (the concentrated type), enough so you end up with a 50/50 mixture of the spec’d volume the car takes. I don’t use distilled water myself, hose water here is pretty good quality, not a lot of lime, but distilled water is probably better.
There is some risk of cracking the block what w/the cold water being added to a warm engine, but never had that happen on any of my vehicles. If that’s a concern you can fill the system with water, run the engine until it warms up, cool it down fully, drain, and repeat several times. Takes longer that way, but it seems like it is a little safer.