It is a simple usual children's ball.
For a start we need to draw a circle. If you are not able to draw a circle, take something round and lead round if there are compasses, take it and if there is no that and another, look at a lesson how to draw a circle. On top slightly on the right draw a small oval, it will be the middle of a ball.
Further we draw strips which differentiate colors. The first we draw which are closer to us, then which move away.
And dorisovyvay only part the middle seen from above. If there are colored pencils, you can paint a ball if is not present, then use a simple pencil to put shadows. Vary extent of pressing that tone was different from dark to light.
There are still lessons connected with a ball:
2. A circus seal with a ball
3. 3D ball