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Before cleaning your touchscreen computer, unplug and power down your device. This will reduce any electrical risks and keep your device a cooler temperature for cleaning. Use a microfiber cloth to clean your touchscreen thoroughly, wiping from side to side. Be sure to wipe around the perimeter of the screen, using your fingernail to press a bit of cloth into any crevices where the screen meets the back. Apply gentle pressure to remove surface fingerprints.  Avoid applying extreme pressure, which can damage the crystals of your LCD. Microfiber cloths can be purchased at camera, technology or eyeglass stores. They are made not to scratch sensitive surfaces, such as your touchscreen. For stubborn smudges, spritz 1-2 sprays of eyeglass cleaner onto your microfiber cloth so it is damp but not saturated. Wipe your screen in small circular motions to remove any oily smudges or fingerprints. Do not spray the cleaner directly on your touchscreen. This can cause the screen to become excessively wet and damage to the electrical components. Use a clean, dry microfiber cloth to buff your touchscreen after using eyeglass cleaner. This will reduce streaking and dry any residual moisture.

Summary:
Turn off your touchscreen computer. Use a microfiber cloth to remove dust. Clean stubborn smudges with eyeglass cleaner. Dry your screen with a clean microfiber cloth.