To prevent finger marks on stainless steel sheets, you can try a few simple steps. Firstly, make sure to clean the sheets regularly using a mild detergent or stainless steel cleaner to remove any existing fingerprints. Next, consider applying a protective coating or film specifically designed for stainless steel surfaces, which can provide a barrier against smudges and fingerprints. Additionally, try to handle the sheets with clean and dry hands to minimize the transfer of oils and dirt. Finally, consider using microfiber or lint-free cloths for cleaning instead of rough materials that can leave scratches or streaks.