1.Pick a cloudy day-Contrary to common belief, a cloudy day is the best day to clean windows. While sunny days help you glaringly see the state your windows are in ,to actually clean windows a dry cloudy day is best . This is because the blazing sun will dry any cleaner you use once sprayed onto the already very hot windows before you get a chance to wipe it off ,making it harder to remove streaks.
2.Clean first then polish- Clean first to remove all the dirt and dust .It might need that the outside windows first need a sweep to remove all the dirt from the window frames. This ensures all the dirt doesn´t turn into a muddy mess when mixed with water and cleaning detergent making your job so much harder .This also means its best to use a separate cloth to dust/clean and then another to polish.
3.When cleaning windows ,the best way to ensure there are no streaks is to clean one side (the inside for example ) vertically and them the other side horizontally. This allows you to see if there are any streaks and which side they´re on
4.Soapy water works best to clean windows .Fill a bucket with simple solution of a few drops of cleaning detergent with water. Just make sure it´s not too soapy as this will leave more marks if not dried properly .
5. Spray the cleaning detergent on the cloth itself to clean mirrors. Spraying straight on the mirror risks the cleaning product to run down and get into the corners that will be impossible to clean . So for mirrors just spray on the cloth and polish to see a sparkling mirror.