1 – Wait for a cloudy day
Although seeing the sun blazing through your, less than clean, windows might inspire you to give them a good clean, you should wait for a cooler and greyer day.
This is because when it’s warm and sunny outside, it can cause your cleaning agent to dry too quickly, leaving watermarks on the windows.
2 – Choose your cleaner…
There are loads of specialist glass and window cleaners out there and everyone has their favourites.
Test a new cleaner out on a smaller pane of glass before using it on all your windows, to check you’re pleased with its cleaning power and finish.
source: express.co.uk