one for primer to cut the stain, two finish coats.
On this project, you notice if you paint one area the brush strokes will mess up the other, so I divide the doors into three parts and paint them in this order. I use a 1 and a half inch sash brush.
First I paint the insides of the louvers, the corners, or the sides of the styles, do this on both ends. Second, with one lay on stroke I will paint each louver. Begin the layon where the end paint is and to the other end paint.
Now, you have the ends painted and the louvers. Thirdly I will paint the face of the door. This way, each painted area will not be interepted by the other.
Let dry and turn over and do the same with the other side.