What's the best road to paint a giant arched ceiling? My place has a high-ranking angular vaulted ceiling- possibly 20 feet glorious....

My place has a high-ranking angular vaulted ceiling- possibly 20 feet glorious. The previous owners told me that thye painted it themselves in times past. I'm not crazy about the dark green color they used- I want a lighter, more neutral sand color instead. Any tips on what tools to use? Since I'm going from a dimness color to a lighter one, what other preps would I need to do? Thanks.
Answers:    Since you don't want to hold to repaint it more than necessary, manufacture sure to use a good point primer and paint, preferably the same brand.
They do rent scaffolding beside mar-resistant wheels at your local tool rental store, but if it isn't a huge ceiling rent a soaring step ladder instead. A 16 footer will allow reaching a 20 foot ceiling for the average largeness person.
sprayer is the best on ceiling,just cover everything first.