I need to clean my aircraft's windows - what do I use?
I assume that your aircraft has acrylic windows. This is a very soft material which is easily scratched and cracks under stress. For cleaning, use these steps:


Rinse with lots of water to remove dust.
Wipe with a wet, soft sponge. Don't press on the sponge and move it in the direction of airflow. Moving the sponge sideways will increase the risk of sideways scratches which are caused by the movement of dirt particles over the acrylic surface. Those sideways scratches will impair vision when flying into the direction of a low sun.
Dry the surface with a chamois leather, again moving in flow direction.


Superficial scratches can be removed by polishing the surface with an acrylic or metal polish. Be careful with sandpaper because this could take off more material than necessary, resulting in optical distortions when looking through the polished area at an angle. 

Never use alcohol or other organic solvents!