Cover the walls with plastic sheeting to prevent the paint from splashing onto them, and secure the sheeting in place with masking tape. Make sure that you place the tape so that it borders the ceiling tightly, along the top of the walls. Cover the floor and any furnishings in the room with drop cloths to protect them as well.
Pour a can of paint in the color desired into a 5-gallon bucket. Add the texture pre-mixture to the paint, and then mix the texture into the paint with the electric drill at low speed. Check the texture manufacturer's instructions for the amount of texture to add to the paint by volume.
Use the ladder to reach the ceiling, and paint a 5-inch-wide strip on all sides of the ceiling. This will make certain that the texture paint reaches the edges of the ceiling where the paint roller might have difficulty reaching evenly.
Lower the painting screen into the bucket of paint. Attach the extension pole to a foam paint roller. Split the paint roller every half-inch with a utility knife; this makes it better able to carry the texture on the tiled ceiling surface. Dip the roller into the paint, rolling it up the screen on the side of the bucket to remove any excess paint.
Roll the paint onto the remaining ceiling area. Work inward from the outside edge where you’ve already applied the strip of paint. Use smooth, even strokes, starting and stopping each stroke in the middle of a tile to avoid leaving ridges of paint in the joints between the tiles.