Take a rectangular sheet of paper
Fold it in half lengthwise
Fold it in half again, then unfold
Fold the top corners down to the center crease
Fold the bottom flap up on both sides
Open the bottom edge and flatten it into a diamond shape
Fold the lower corners of the diamond up on both sides
Open the bottom edge again and flatten it into a smaller diamond shape
Pull the top corners apart to form the boat
Adjust the sides and base so it sits evenly on water