The only way to get better, is to keep practicing it. I never use to shade, and I’m still learning. With my art, I do simple stuff and I follow basic steps that apply well for me.
Why not try this:
Before you do any shading, figure out where your light source is. Basic knowledge when shading.
Here, we have the light source above and in front. ABOVE an IN FRONT. So you gotta think how the shadows would go. He’d be pretty well lit.
Remember, the nose isn’t flat, that’s going to create a shadow on his face, unless it’s right in front of him and not from the side like it is.
So how would it be from the back?
He’d be more shadow than light.
Another tip for shadows:
Some people might draw shadows on after colour the flat colour, but if you know there is going to be a lot of shadow, much more than lit up skin, try this way:
Colour with your shadow colours, and fill in the light instead.
I filled it in with light this time, instead of filling in shadow.
But really, you just gotta take a big leap and adventure with it. That’s how I got to where I am and I still have far to go.
And also try shading with different colours. In these pictures I shaded the skin and clothes with pink set to multiple, and the hair with purple on multiple.