Painting the ceiling above a stairwell can be difficult. Not only is the ceiling too high for you to reach, but you need to balance on the stairs. Using a painter's pole will work on the flat portion of the ceiling, but painting the corners gets tricky. One of the best ways to achieve a good paint job over stairs is to use a scaffold. A scaffold consists of a raised flat board for you to stand on, supported on either end. Creating your own scaffold is easier than it sounds and then you'll be able to reach even the highest corners of your stairwell ceiling.
Wedge an extension ladder against a stair close to the bottom landing of your staircase. Raise the extension ladder up to almost the height of the lowest portion of the stairway. Rest the upper portion of the ladder against the wall opposite the top of the staircase.
Set up a stepladder on the top landing of your staircase. Make sure the legs are far enough away from the edge of the stairs to avoid it moving forward and causing injury from a fall down the stairs.
Place one end of a 38 x 286 mm board onto the bottom rang of the step ladder and the other end onto whichever rang of the extension ladder will make the board most level. Hold either end of the board to the ladder with a C-clamp.
Nail a vertical board to the first board if you are spanning the stairwell more than 2.4 metres (8 feet). Cut the board to the length spanning from the bottom of the 38 x 286 mm board to the top of the middle stair.