Cleaning windows does not need to be hard, you just meed to know how to do it.
Never clean windows on a hot sunny day. The cleaning solution will dry very quickly and you will end up with streaks on your window. Cloudy days, or early mornings are best.
You do not need to waste your money on expensive cleaning solution. Instead just use normal dishwashing solution. I find that the environmentally friendly solutions work the best.
Once you have cleaned the windows from both sides, check the, out from a number of angles. This inspection will help give you professional results.
You do not need much pressure on the squeegee. If you press really hard, getting great results is impossible. Just use light pressure and keep it constant.
Hope that helps. Enjoy the view.
The creator of this guide has not included tools