1. Mix 1 teaspoon of dishwashing liquid (perfer lemon scent) to 1 liter of water.  Pour it to a spray bottle and you have the most power and best window cleaning chemical around.

2. Old newspaper or old cotton t-shirt are some the best rags that window cleaner expert use.

Try this out and tell me what you think.  Try it on the mirror in your bathroom, car window, house window, etc.