When using shading to create an aspect of lighting, it's necessary to choose the right weight of the lead, and to hold the pencil in the right way.
This video shows some of what is needed, and should further clarify the process for you aspiring artists.
Bear in mind that imagination is also important, and that technique is just a road traveled to get you to the home you truly want to build with your imagination.
Light is sooooooooooooo important. Art that lacks the use of lighting is often very flat and dull. So unless that's what you're striving for, best to learn how to use light in your work, even in the simplest of things.
Best and enjoy.
Learn how to draw by finding out which pencil to use for specific light and tones. All the tips, tricks and techniques on how to draw and which pencil to use. Online drawing lessons brought to you by Vir2l Art Student - www.vir2l-artstudent.com.