Carciphona is a high fantasy webcomic/manga written, illustrated and published by me ^^ Set in an era where magic is forbidden, the story follows a young sorceress who, despite possessing more power than most could even dream of, could not grasp the simple peaceful life she longed for. But all this will change, whether she is ready for it or not. Start reading from the beginning.
I think what Shilin told me before is she uses several different shades: white, light gray, gray, dark gray, and black.
From what I see, most things use the same screentone pattern over it. It's best to shade all the colors on a single layer, then in photoshop edit the layer, choose a screentone pattern, and then reduce the opacity.
It's a lot of things to do, but that's something I've noticed and used.