Avoid the sun
Because when we wipe in bright sunshine, we often end up annoyed by streaks and getting the windows streak-free seems almost impossible. This is because the cleaning products dry too quickly on the windows due to the heat.
Remove coarse dirt
Remove dust and pollen with a soft brush, use a wet sponge for stubborn stains. Then prepare window cleaning solution. Pour 3 liters of lukewarm water into a bucket, add 1 splash of washing-up liquid (do not use balsam washing-up liquid as it forms a film), 1 capful of white spirit and a few drops of glycerine. Do not use glass cleaner as it sticks.
Ensure a shine
Soap the windows thoroughly with the lye. Wipe with a microfiber cloth or sponge in a circular motion, first from top to bottom, then from left to right. Soda or a little ethanol can help to remove hard-to-remove smear films. Remove the dirty water with a squeegee, then wipe with chamois leather to clean the window streak-free.
Extra tips
If streaks are still visible on the window, polish them away with an old pair of nylon tights. Do not use newspaper as it leaves behind printing ink. Remove limescale stains with vinegar.