So here is my new video on shading techniques. It will show you different ways with which you can enhance your sketching skills.
First of all you need to create a rough layout of the object. Keep the pencil strokes as light as possible, so that it is easy to make corrections later on.
Once you are done with your layout, you can begin with the shading. Shade the lighter tones first. Ensure that your shades move in the direction of lighting of the object.
After giving light shades, gradually darken the shadows. Continue to intensify the darker shades till the sketch is complete.