Download the Beluga template, print, and cut out the pieces you need.
Optionally: If you want to make it look like the Beluga is in the water, cut a thin strip of blue paper and glue it to the top of the brown paper bag flap. Glue the larger blue rectangle to the main portion of the brown paper bag.
Glue the Beluga head to the flap portion of the brown paper bag.
Position the flippers on either side of the body, around the middle, and glue them to the back of the body.
Finish the puppet by gluing the body onto the blue rectangle.