Looked up U Tube and followed instructions posted by several people. At first windows looked clean but l did notice hairline scratches which really bothered me. So l used the Karcher with lighter strokes..but still have marks on our windows.
Next day the sun shone and we saw all the marks left where the line strokes overlapped and along the bottom where the blade could not go to absorb water.
Did them all over again and used a dry micro cloth to buff but still not as good as the product promises!
Called in the professionals to clean all our windows in and out next week!