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Fill the bottle slowly, so that the soap doesn't bubble up and run over the top. It's best to use lukewarm distilled water rather than tap water, since your tap water may contain minerals and other impurities. You can find various brands of dishwashing detergents at your local grocery store or pharmacy. Before applying dishwashing soap to your plasma screen, read your TV's warranty. Make sure that it won't be voided if you clean the screen with soap. Aim the liquid spray away from your TV so you don't risk spraying the soap solution directly onto your plasma screen. Then, squeeze the trigger 2-3 times to lightly dampen your microfiber cloth. If you spray too much liquid into the cloth, you can wring it out over a sink to remove excess moisture. Put your index finger in the cloth under the damp region. Press your finger lightly against the spot on your screen. Move your finger in a circular motion to wipe the dishwashing soap solution onto the stubborn stain. After a few wipes, the stain should come off. If the screen is still dirty, try adding another 2-3 sprays of soap solution onto your microfiber cloth. And wipe the screen again. Press lightly on the screen as you wipe it clean. Don't apply a lot of pressure, or you may damage the plasma. Once you've spot-cleaned the screen and have removed the stubborn stains, use 1 more microfiber cloth to dry the spots you cleaned. This will prevent new bits of airborne dust from sticking to the screen. If you find that the screen is still slightly wet and soapy, you may need to slightly dampen a microfiber cloth with distilled water. Use the cloth to wipe the soapy residue off the screen.
Fill a spray bottle with water and 2-3 drops of dishwashing detergent. Spray 2-3 squirts of the liquid onto a microfiber cloth. Use 1 finger to wipe the stained spot on your plasma screen. Wipe the screen dry with a clean microfiber cloth.