Take a rectangular sheet of paper
Fold it lengthwise down the middle
Unfold it
Cut along the center fold from the bottom up, stopping about one-third from the top
Fold the two top sections outward to form the helicopter blades
Fold the bottom section upward to make the body
Fold the lower part again to create a small base or weight
Open the blades slightly so they can catch air
Hold the bottom and drop the paper helicopter from a height
Adjust the blade angles if needed for better spinning