if you’re fine with slowly destroying the serrations, the same way you sharpen any knife!

actually though serrations are generally only cut from one side, so you can very carefully sure up and hone the flat side. the opposite you would do with something like a flat ground tanto.

if you wanna be REALLY careful you can use a round sharpener that matches the size of the serrations and hit each one individually. this will also redefine their points if they’ve been dulled by less careful sharpening.

although since it’s also a cutco knife you can just send it to them for free sharpening, you just have to pay for postage.