I am still learning (trying to) this knife stuff.
The way I have been doing it is sanding by hand from spine to edge, using a small sanding block to keep the paper relatively flat. I will use a flat piece of wood or a flat gum eraser as the sanding block. The blade has already been sanded to 600 grit on the belt sander. By hand I start again with 600 grit. I then proceed in order from 600 to 2000 grit. That means by hand: 600, 800, 1000, 1200, 1500, 2000. I then (very causiously) buff it using an 8 inch buffing wheel coated with buffing compound. I have always sanded and buffed from spine to edge. Very important to me is that I never make the cutting edge untill all sanding and buffing is complete. Otherwise can be extreme danger.
I find my finer grit papers (those grit papers smaller than 600) at auto parts stores such as NAPA. Eight hundred seems to be the least likely to find for me.
Roger