TRSE How To Draw Tutorials:
Drawing in 3D
Drawing the pictures in 3D is somehow tricky, and it takes a great deal ofl practice and some understanding of geometry to draw the pictures in 3D. Let's get over the basics of drawing in 3D. See this picture?

In the real world, everything are in 3D. Notice how a box outlined with red lines are arranged in 3D. The point where the lines meet are called "focus". Let's say we're flying over the railroad rails. When we look downward, we can tell that they're parallel. When we land on the ground right between the railroad rails, we look forward, and the railroad rails seem to meet at one point in a faraway place as if the rails are not parallel. Of course, the railroad rails don't merge with each other, and they stay parallel to each other over its entire length. The Focus is the limit of how far we can see. So our eyes make anything in the back seems to be smaller than anything in the front. Now look at the next picture very carefully.

Notice that the horizontal lines are very close to each other in the back whole those in the front are further away from each other. You can notice all of the 3D when you're walking down a long hall in a school or someplace big. Let's hit the "Next" to demonstrate drawing the characters in 3D.