Summarize this article in one sentence.
If you can draw a triangle, you can easily make a cone. Draw a V shape or sketch it upside down as though you're starting to draw a triangle without its base. Make the V shape as large as you'd like the cone to be. Rub the tip of your pencil back and forth along 1 side of the cone until it's heavily shaded. Apply a little less pressure as you shade towards the middle of the cone and use a light touch on the opposite side. Add a little more shading along the bottom of the cone near the darker side of the cone.

Summary:
Sketch a V shape using a pen or pencil. Darken 1 side of the cone and gradually shade to the opposite side.