And i would also be looking at a training course to go on!!!
Cheers
Alan
you honestly do not need to go on a course, pratise on your own windows for a hour or so and you will get the knack of it
you could allways ask a local window cleaner to watch him for a hour or 2
i clean mine like this
brush around the edges of the glass
brush up and down moving across the glass
1 last brush of the top of the pane
then rinse ( pull brush away from glass a few inches ) moving left to right whilst moving down the glass
you dont need a window cleaninfg school for that