Rooms with a sloping wall do not necessarily have to form an insurmountable obstacle. With a bevel or a folding rule you can easily solve any problems. Measure the angle of your wall. Draw the angle onto your plank and cut on this line. Break off the corner, with the decor side facing upwards.
Try to alternate the alignment of your short joints. Start a new row with planks left over from their previous row and make sure that the short joints of your planks always stagger by at least 30 cm. This will ensure the best possible result.