First I draw a sketch. I highlight the general composition and features of objects
Then I draw the line. I paint the canvas and paint line on a separate layer. I choose the color of the line a bit darker than the color of the object that I paint.
Next, I add shadows and glare. The color of the shadow I try to choose between the color of the line and the color of the object. Glare should be the lightest on the object. You need to mentally choose the point where the light shines, and then draw the shadows
Be sure to pay attention to the details, draw them, it will make your work live and give it a finished look