For routine dusting, a feather duster is all that you should need to dust the face of the screen and along the top of the TV. To remove fingerprints, try using a dry microfiber cloth. Be careful not to apply too much pressure while cleaning to avoid scratching the surface. For heavily-soiled spots, cleaning products are available that are specifically made for that purpose.
Use cleaning products that contain no alcohol and no ammonia.
Use a microfiber cloth for best results. Another thing to consider is that dust will sometimes build up in the air vents along the top of the rear cabinet. You could use a vacuum with a brush attachment to clean these vents. This will allow for proper heat dissipation and ventilation.