1. First, draw the general outline of the apple and find out the dark side. Remember to draw a long line, summarize the overall situation, find the approximate position and ignore the details.

2. Find out the dividing line between light and dark, that is, the boundary between light and dark parts in the sketch. Specifically, you can look at "What is the boundary between light and dark" and spread a big tone of light and dark.

3. Spread a large color fixing surface. Three major surfaces: After receiving light, an object can be generally divided into three bright and dark areas: bright surface, gray surface and dark surface. Simply put, it is "black and white ash".

Bright side: the side that is fully illuminated by light is called bright side;

Dark side: one side of the backlight is called the dark side;

Grey surface: The part between the bright surface and the dark surface is called grey surface. Note that the gray surface is the transition between the bright surface and the dark surface, so it is natural to depict the transition.

4. Depth depiction strengthens the sense of volume, texture and space. Continue to depict the body sense and subtle changes of light and shade of the object apple by means of flat cable, increase the expression of apple texture, and express the sense of space by depicting shadows.