First you need to draw a vertical line on the wall with a plumb line, which should touch the corner of the bathroom. Then we also draw a second line, which should be located in the parallel with the first, but at a distance to it 2.5 cm. Then the first line can be erased. A plumb line is applied to the corner and a hammer, point or other control mark is placed on the floor. After that, draw a square, in which one angle rests against the indicated position and has sides 2.5 cm long. This square should be placed strictly at the bottom of the sides at the bathroom. Accordingly, measure the distance that is necessary in order to create a reserve for the thickness of the panel of the screen itself and for the sake of its skin (for example, tiles). After one of the angles at the square, you need to draw a line diagonal from a point opposite to the one marked with a plumb line — to the base of the lines applied to the wall.