Has it been waxed ad if so how long ago. If not use a product called uma,it is a urethane modified acrylic. Check your local paint store. Follow application guide.

Actually mine was done with a trowel and a Lyme paint by a faux painting artist. I it has light and dark areas in a pale yellow color. Here is my fear ... We would like to go to a deeper color without changing the finish but we are afraid that it will look like a bad paint job. Our painting company says this will work,( not the original artist) I am nervous this is a 20 foot ceiling room with beams that flows into the kitchen and hall.