Window screens always get pretty dirty after awhile, and they reduce the amount of sunlight that comes in your windows. Here's how we like to clean our screens:
If you have an air compressor or a can of compressed air, GENTLY blow dirt and debris out of your screens. Using a wet/dry shop vacuum cleaner also works well for removing dust and debris from both the screen and the channel in the window.
First, remove the screens. Mark one of the top corners of each so you'll know which direction the screen faces when you replace it. You can also mark inside the channel where the screen goes and match the marks up later.
Using a hose, shower nozzle or large heavy-duty sponge, gently wet the screen thoroughly.
If your screens aren't too dirty, use a soft-bristle brush to clean them (CAUTION - a firm-bristle brush could tear the fabric). Begin by cleaning the spline, where the screen is connected to the frame. Start with a dry brush, then dampen the brush and clean the screen more thoroughly.
* 4 Tbs. dishwashing liquid
* 1/4 cup ammonia
* 3 Tbs. borax
Mix the items above with warm water in a 5 gallon bucket and mix thoroughly.
Dip a sponge in the solution, lightly wipe it all over the screen until there's a nice sudsy coating on the screen, then lightly work the suds into the screen with a soft-bristle brush. After you've brushed away the dirt and grime, gently rinse the screens with a garden hose, shake them slightly to remove water.
Lay screens on absorbent towels or stand screens on one corner to allow the water to drain from the spline and frame. You might also want to wipe them dry with a clean, dry towel to remove any remaining dirt.
While each screen is out, clean the channel in the window. Use a cloth-wrapped pencil tip or screwdriver.
If you wish to store the screens for the winter, wrap them in sheet plastic, which comes in rolls and is available at most home-improvement centers. This will prevent bugs and other pests from getting into the clean screens.