I have done both. On a spinner, I get great results and its very easy to get the exact shine level you want based on how much you apply, how hard you push and for how long. By hand its a different story. It isn't the most abrasive polish out there so by hand you really need to put some elbow grease into it to get a decent finish and I end up using a ton of the polish. It's also very hard to get the finish even across the whole ball. I had to hold the ball in the light and assess the evenness of the finish by how well I could see my reflection. If I have to do it by hand I prefer to use the bottle of Storm Xtra Shine I have since it's a little more abrasive and a little easier to apply. I still prefer to use a spinner in either case though.