- KME (or equivalent) knife sharpener (link)
There are two tricks to getting a really sharp blade: Slowly working your way up in grit and stay at a constant angle. Sharpening kits like the one mentioned above let you set and keep the angle you want. After things are dialed in and your blocks are oiled, it’s trivial to get a consistent edge. It’s not a purchase you’ll regret.
The pocket knife pictured below went through the following grits: 150 > 300 > 600 > 1000 > 1500 > strop. It was challenging to work on such a small knife, but it’s incredibly easy working on larger blades.