Help please) How should artists accurately render the type of fabric used in their garments?

They should use value and layers of color,

They should use only one color per Item.

They should work in a dark room with dim light.

They should add details to the figure.

Acurious child asked his mother: “mommy, why are some of your hairs turning grey? ” the mother tried to use this occasion to teach her child: “it is because of you, dear. every bad action of yours will turn one of my hairs grey! ” the child replied innocently: “now i know why grandmother has only grey hairs on her head.”