How did the ancients make inkstones?

What is needed is an inkstone. The material is she inkstone or Duan inkstone. Then a meat cleaver. Carving knives can be bought in antique painting and calligraphy shops. But it is best to buy knives for stone carvers, not seal cutting knives.

Decide the pattern you want to carve according to the material, then outline the pattern you want to carve with a colored pen (a brush dipped in ink or chalk), then carve it, and then polish it with sandpaper.

I suggest you don't bother, just go to the supermarket and buy a jiaozi-eating disc, and then come back to fill the ink. If you really study ink painting and practice calligraphy, it's really a waste of time.