First you need to mark on two walls: on one and on the other, opposite. To do this, it is necessary to measure the desired distance. Two people are located on both sides of the room. Then the thread is applied, and the line is beaten off. If it is necessary to apply two or more levels, the marks on them, respectively, should be different. They can be marked with different colors or dashed lines. This will help to easily install the ceiling coating.
