Start with a rectangular sheet of paper
Fold the paper in half lengthwise
Crease firmly, then unfold
Fold the top two corners toward the center line
Fold the new slanted edges toward the center line again
Fold the plane in half along the center crease
Fold each wing down so the top edges line up with the bottom edge of the body
Make both wings even
Press all creases firmly
Hold the plane and throw it forward gently