get a harris pole from b+q around £15-£20, wash with applicator change add blade , after blading add scrim to detail the top and edge to prevent drips, the wagtail does this job but ive never got that far , go onto you tube you will be suprised as to what you find, just type in window cleaning and you will be there all day., its surprising how much time you waste once you get online.. I BETTER GO.