To speed up the process, try a wire wheel, attached either to a bench grinder or a handheld electric drill. The wire wheel also produces a sheen that's hard to match with hand rubbing. If you do use a drill attachment, clamp the pruners in a vise for safety. To sharpen bypass pruners, you'll need a small, fine-grit diamond file. Sharpen the beveled side of the curved blade.
Anvil pruners are different.
The sharp cutting blade on them descends to meet a soft metal anvil. Sharpen the blade with a double bevel, which is similar to some knife blades. Run the file parallel to the blade, from the base to the tip. Be sure to keep the blade edge straight. Replacing handles .