Step 1: Read my post Perspective 101 and watch the video Empire of the eye:The magic of Illusion.
Step 2: Grab your camera and go for a walk. See if you can find some examples of one point perspective in your neighborhood. Any digital camera will do, even the one on your cell phone.
Step 3: Print out your pictures and grab your ruler, a piece of tracing paper and a pencil. Extend the lines of perspective to find the vanishing point. You can also use a dry erase marker and a piece of clear plastic or draw directly on your photo.
Step 4: Start looking for examples of one point perspective wherever you go. Follow the lines of the buildings around you with your eyes and try to figure out the vanishing point and horizon line. Get into the habit of bringing a sketchbook or a camera with you whenever you leave your home. Start documenting examples of perspective in the world around you.
Step 5: Look at pictures by famous artists who utilize perspective. Print out the pictures and extend the converging lines. Draw the horizon line and vanishing point directly on the paper.
School of Athens by Raphael
The Last Supper by Leonardo Da Vinci 1495–1498