Take a rectangular sheet of paper
Fold it in half lengthwise
Fold it in half again, then open it back up
Fold the top corners down to the center line
Fold the bottom flap on the front side up
Turn it over and fold the bottom flap on the back side up
Open the bottom edges and flatten into a diamond shape
Fold the bottom corners of the diamond up to the top point
Open the bottom edges again and flatten into a smaller diamond
Fold the bottom corners up again
Open the bottom edges and flatten once more if needed
Pull the top corners apart to open the boat shape
Adjust the sides and base to form the paper boat