I do like how you do not over-do the shading.

ur shading’s just alright - I’d advise adding one more darker shade to your shadows for emphasis

maybe a more important question is what you’d like to accomplish with your shading e.g. something simpler or something with more detail. that’ll depend on the subject of the skin you make and the desired mood you wanna portray

Id also recommend thinking about colour choices and colour depth for you darker shades/highlights. the right colours can really make simple shading shine

Im on mobile rn but i can grab some links later : )

If you want a boost up your shading ,
Than this might help you.

Skins don't really need fancy shading to be good IMO and your style seems to be rather simple like cel-shading