The optimal way to clean your windshield is to give it a proper bath. Lots of water and a little dishwashing liquid work well. But make sure you use a clean rag, preferably made of soft cotton or microfiber, to wipe the surface. You can also safely use shop rags, but avoid paper towel or dirty rags. If in doubt, ask if the material can be used on acrylic. It is also important to rub the surface gently straight up and down. Don’t use a circular wiping motion. You may end up with a permanent halo in front of you.