Not My thing but if I were to do it I think a Dedicated 12V spot sprayer that didn't have to be cleaned after each use would be the way to go. I would also try and use a Pressure washer gun with a Flat Fan like a AIRLESS PAINT SPRAYER. I don't know, but I am guessing 2 to 3 gallon a thousand maybe more is needed to get Coverage.
From the Grass paint Jobs I have seen, I think Brown is Beautiful by comparison.
You can lead a Donkey to water but you can't make the Jackass Drink
"As Americans you have the right to be stupid." John Kerry
"Life is tough, but it's tougher when you're stupid.” John Wayne.