A three-colour starting point for skin shading
Use a base, a shadow and a highlight to make small shapes easier to read.
Begin with a colour role
Choose one base colour for a garment, then a darker shadow and a lighter highlight. This is a design exercise, not a limit imposed by Minecraft. Giving each colour a job makes it easier to see whether a pixel describes a fold, an edge or an accidental mark.
Keep the first test small
Try a cuff or a short section of a hoodie before shading the whole character. Keep most of the area in the base colour. Add a short shadow along an edge and a restrained highlight nearby. Compare the small sample in 3D before repeating it elsewhere.
Avoid outlining every pixel
A dark border around every face can make the body look like separate boxes. Let some edges remain quiet. At this scale, a small cluster of pixels is often easier to read than many isolated bright dots.
Check adjoining faces
A stripe that ends at the front edge should meet the intended pixels on the side. Rotate the character and inspect the seam. A pleasing flat pattern can still look disconnected once it wraps around an arm or torso.
Review at normal size
Zooming in helps you place pixels, but zooming out helps you judge the design. Save the original and compare one change at a time. The colour choices here are editorial suggestions; the best palette depends on the character and the effect you want.