Not a stupid question. We have all asked it at one point or another.
Carnuba Wax in solid bar or puck form, applied with a sewn muslin buff, either mounted on a variable speed motor or a drill.
Get the buff up to speed (medium-high), gently apply the bar/puck to the wheel, and the friction of the buff will pick up the wax. A little goes a long way. You won't really see it on the buff but you'll smell it. Then holding the pipe in your hands, pass it along the wheel lightly and slowly. Hold firmly! It goes on readily but you can build up too much. Then use a flannel buff to remove excess and smooth it all out.
For my smooth pipes and stems, I use hard caranuba on a buffing wheel, followed by a wipe down with the mostly dry cloth I use for "floor waxing" my briars. I've used a spray "Briar pipe wipe" in the past, but I seemed to be repackaged Pledge-type furniture spray. The shine burned off with a little heat and it smelled strong.