Never had to actually sharpen mine, which I've had since '93. Only had to dress the edge, and I do that lightly after every use. I use the white rod of a sharpmaker and do it free-hand. I don't like jigs. (tried them obviously) I have better success just eyeing it and going by feel. If a ceramic rod isn't close, I use one of those pocket diamond stones, extra fine. They're green and fold like a balisong.
I might strop it a bit after...Works for me.
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"When loss and gain are alike to one, that is real gain.."