How do I white wash or paint a dark rough wood ceiling?

Water down paint with water...50/50 mix. Use a four to six inch paint brush. Dip the paint brush in the paint. Off load most of the paint to paper towels. Then dry brush the ceiling.

Cover EVERYTHING from the ceiling down with dropclothes, and use duct tape to close sides and gaps. You can even create a passage through with the drop cloths and tape, but be sure the passage can be closed during painting. I would buy or rent a paint blower if you are doing the whole ceiling. A day or two later, you could paint the walls, but cover the ceilings, too, this time. Best wishes, Jewell

If you add a little bit of water to white paint it should go on pretty easy. Then just wipe off the excess.