You have made a good effort to create a ball shape. However, in my opinion, explaining this technique through words is not easy. Because whoever has never drawn before will first need to practice different shapes. And then, they will need to understand the details of spotlight and shades. After that, controlling the pen strokes and ink quantity is also important. And most importantly, to achieve the desired result, setting the brightness, contrast, and exposure of the final result is necessary. Because just a camera picture cannot show the result of your drawing, unlike what it would look like after editing.