From Flat to 3D
So far we have been drawing buildings from the front, which makes them look flat like a picture on a wall. But real buildings are three-dimensional — they have depth! Let us learn a simple trick to make your buildings look 3D.
The trick is to show TWO SIDES of the building instead of just one.
Step 1: draw your building front as usual — a rectangle for the wall.
Step 2: from the top-right corner and bottom-right corner, draw two lines going up and to the right at an angle (about 45 degrees). These lines show the SIDE of the building going back into the distance.
Step 3: connect the ends of those two angled lines with a vertical line. This is the far edge of the building.
Step 4: for the roof, draw the triangle on the front, then draw angled lines from the peak and the other top corner going back to the right. Connect them to the top of the side wall.
Now you can see TWO walls of the building — the front and the side! This makes the building look like it is popping out of the paper. Add windows and a door to the front, and maybe a window or two on the side wall.