Nakamura Lock

Steps

1. Fold in half lengthwise, unfold.
2. Fold top corners to the center crease.
3. Fold the top point down to the edge of the corner folds.
4. Fold the top corners to the center crease again.
5. Fold a small triangle tip up to lock the layers.
6. Fold the plane in half.
7. Fold wings down to make a medium wing.
8. Adjust: wings level, tiny upturned tips.