To remove dust, there is a cleaning cloth supplied. Take care to touch only one side of it and use the other side to clean the tile. This will help stop finger grease from building up over time. If a replacement cloth is required, you can contact an accredited service centre, or use a fresh cleaning cloth suitable for glasses.
If you suspect there is a greasy residue on the tile, breathe on it. Any grease will show up as a slight rainbow sheen. This can usually be removed with a fresh cleaning cloth. Iso-Propyl Alcohol can be used to remove larger amounts of grease. Ensure that the IPA is removed from the tile with a lint-free cloth while still wet. Allow the tile up to an hour to settle before use.
If available, dry, clean air from a compressor can be used to remove dust.