Suppose you were to look up at the sun or a lightbulb. Sometimes you would be able to see the light beams. This picture shows you where the light beams would be.
Here are the materials I used. I used an HB pencil, mechanical pencil, 6B pencil, tortillion and a kneaded eraser. I also used a ruler but I forgot to put it in the picture.
Now on to drawing. Draw the basic shapes of the 3D objects. The cube is a straight line, the sphere is a curved line, the cone is an angle, and the cylinder is two straight lines.
Next, turn those lines into shapes. For the cube, draw a square. The sphere is a circle, the cone is a triangle, and the cylinder is two curves connected to two straight lines.
Then draw actual 3D shapes. Draw a cube, sphere, cone and cylinder. I drew dotted lines to show you the other sides, faces and vertices just to help you. (You don't have to draw the dotted lines if you don't want to.)
Now we are going to add in the tone of the cube. Tone is the overall lightness or darkness of an object. Shade in the front face and side face of the cube with an HB pencil. Then blend in the tone with a tortillion, or, if you don't have one, use a cotton ball or q-tip.
Do the same thing to the cone and cylinder, but shade the whole thing.
Also do the tone to the cylinder, but don't shade the top face.
Now we are going to do the actual shading. All you have to do for the cube is shade the side face darker than the tone. Don't do anything to the top and front faces.
Next, shade the cone and sphere. Start from the darkest on the left side and then gradually get lighter as you move toward the right side. Then erase the left over tone with your kneaded eraser.
Then do the same thing to the cylinder, but don't do anything to the top face.
Now we are going to draw the cast shadows. Cast shadows are shadows that appear on the side away from the light. With your 6B pencil, add in the shadows.
Oooh, my favorite part! We are going to make these look like actual 3D objects. The cube is a block of wood. Use the ruler to draw lines about 1 cm apart. Then draw wood patterns inside them with the mechanical pencil.
The sphere is a tennis ball, and the cone is like a tent thing. With the mechanical pencil, draw the two curves on the sphere and then little lines for hair. Then draw little lines at the top vertice on the cone and then draw the tent opening. Shade inside the opening with the 6B pencil. Then draw lines down the cone.
The cylinder is a bucket. Draw lines going down it, and then draw curved lines. For the handle, connect another curved lines to the original curved lines.
Here is what your 3D objects should look like when you are done. I hope you like it!