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Use a ruler to draw the horizon line on your paper. Mark 2 vanishing points on the horizon. Draw 3 or 4 perspective lines that extend from each vanishing point. Use the perspective lines to draw the flat top of a box for a practice project. Make vertical lines to connect the box from a two-point perspective. You've finished two-point perspective.
Once you've decided where you want your viewer's eye level to be, lay a ruler there on your paper. Draw a light line across the ruler to create the horizon line. Place the horizon in any part of your paper, not just in the center. You could make the horizon in the upper 1/3 or lower 1/3, for instance. Draw 2 small dots on the horizon as far apart as you'd like. Although there aren't rules about where to position these points, keep in mind that symmetrically placed points don't look as natural. For the most realistic-looking perspective, try to place the dots so they're off-centered. They can even be outside of the paper! Try putting 1 vanishing point near 1 edge of the paper on the horizon and make the other point off of the paper on the horizon. To do this, make a mark on your work surface or tape down a scrap piece of paper next to your drawing paper. Place your ruler on a vanishing point and draw a light line to the area where you want to put the subject for your drawing. Then, make 2 or 3 more lines from the same vanishing point. Repeat this for the other vanishing point so all of the perspective lines from both points come together. If you placed a vanishing point off of the paper, you can still put your ruler on it. Pull the ruler so it stretches onto your drawing paper. Then, you can make the perspective lines. Now that you have a grid, it's much easier to draw your subject. To practice two-point perspective, draw a box or rectangle along the perspective lines. This will make the flat top of your box. Once you become comfortable with drawing simple shapes in two-point perspective, you can move on to asymmetrical objects. Place your ruler vertically so it's perpendicular to your horizon line. Then, move the ruler so it's at a corner of your box and draw a straight line down. Use the ruler to make straight lines that close off the bottom of your box. Two-point perspective is great for drawing items in a still life or distant buildings. Read on to learn about adding a third vanishing point.