Draw a tall rectangle for the traffic light body
Round the corners slightly
Add three equal circles inside the rectangle
Place one circle at the top, one in the middle, and one at the bottom
Draw a small cap or hood above each circle if desired
Color the top circle red
Color the middle circle yellow
Color the bottom circle green
Outline the traffic light with a dark line
Draw a pole extending downward from the bottom of the rectangle
Add a base or support at the bottom of the pole