We use an orbital sander starting with a coarse 80 grit paper and then move to 100, 120, 150, 180 and 220 grit papers. It’s helpful to make a drum holder by screwing in some scrap carpet between two sawhorses. This will hold the barrel at a good height and the carpet allows you to spin the barrel to the next section. Spend about an hour with each of the grits, possibly changing papers once or twice to make it all the way around. We usually sand outdoors or where the lighting is good so that the grain is more visible. On some of our drums, we have put a stain on the barrel at around 120 grit and then sand it all the way off. This is a good halfway point and will not only raise the grain but will show you that you have sanded the entire barrel at 120 before going to the finer papers.