The best you can do is to get the fine scratches running all the same way. I have had some success with diamond grit paste on a polishing mop. but the same still applies. I have a friend who works in the stainless steel fabricating industry and they use a diminishing series of carborundum grit and wax to achieve a mirror finish. The amount of wax in the final finish is the reason it is sometimes difficult to get cermark to adhere properly.
Hilton Lister. NZ
GCC Spirit 60w. Meistergram 912, Gravograph IT, Old Roland Vinyl Cutter, Hand engraving, Retired