If you're not comfortable with using the Sharpmaker, then a round or tapered diamond rod (or round diamond file) should work for resetting the edge in the serrations. And for touch-ups beyond that, a round or tapered ceramic rod would keep it tuned up, with less metal removal. Both the diamond and ceramic will handle 440C easily. Use the rod on the scalloped side (assuming they're not ground into both sides), and then strop off the burr that folds to the back (flat) side of the edge. Much easier to remove the burr only from that side. Stropping on firm/hard wood, with a rouge compound (like white rouge in aluminum oxide) will work very well with 440C, quickly removing the burr and polishing as well.
There is a certain 'touch' with which the Sharpmaker or other V-crock device can also work very well. I've grown to like using mine for serrations, lightly drawing the blade down & across the rods in the same fashion as used for plain-edged blades. The key is maintaining a VERY light skimming touch at the correct angle, so the edge makes kind of a 'buzzing' or zipper-like sound across the corners of the rod, accompanied by a ticklish, vibrating feeling in the fingers. If it sounds or feels too choppy or clunky, that means the angle is probably off or pressure applied is too heavy. Darkening the scallops within the serrations with a Sharpie can help with seeing where the angle is right, with the ink coming off just at & behind the apex of the edge in the scallops. The Sharpie will be helpful in the same way, if used with one of the round/tapered rods mentioned above.
