from the Surface Support Site
[h=2]Touchscreen care[/h]Scratches, finger grease, dust, chemicals and ultraviolet light can affect the performance of your touchscreen. Here are a few things you can do to help protect the screen:
Clean frequently. The Surface touchscreen has been coated to make it easier to clean. You don’t need to rub hard to remove fingerprints or oily spots. To avoid scratches, use a soft, lint-free cloth to gently wipe the screen. You can dampen the cloth with water or a lens cleaner, but don’t apply liquids directly to Surface. Don’t use window cleaner or other chemical cleaners on Surface.
Keep it covered. Close the cover while you’re on the move or not using Surface.
Keep it out of the sun. Do not leave Surface in direct sunlight for an extended period of time. Ultraviolet light and excessive heat can damage the display.
[h=2]Cover and keyboard care[/h]The Touch Cover and the Type Cover require minimum care to function well. To clean the keyboard, wipe with a lint-free cloth dampened in mild soap and water. Don’t apply liquids directly to Surface. Do this often to keep your Touch Cover or Type Cover looking great.
If the spine or magnetic connections of your cover get dirty or stained, apply a small amount of isopropyl alcohol (also called rubbing alcohol) to a soft, lint-free cloth to clean.