As polished as possible? You're going to have to get a buffer and wax, learn the technique, and become adept at buffing--not as simple as it looks. Even experts sometimes round off edges, soften nomenclature, maybe even have the pipe snag and go flying across the room. I just use Paragon wax on the rare occasions when I think a pipe ought to look more shiny. It's applied with just a rag, and works quite well. Beware waxing sandblasts and rusticated pipes--the stuff goes down into the crevices and looks horrible.
I don't know what Ron Powell (Cartaphilus on this forum) uses, but his pipes are the most blindingly shiny I've ever seen. I suspect he just knows how to do it; no magic, no secret ingredient.