Set up your sculpting station and arrange your reference images so that you can look at them as you sculpt the whale. Use a photo showing the entire whale to take precise measurements with the ruler. Double the measurements you take from the photo if you want to create a whale that is twice the size. Use about 2 pounds of clay if you want to make a sculpture about 10 inches long.
Draw a line 10 inches long on paper and mark the location of the whale's features along that line. Mark where the mouth ends, the location of the eye, flipper, dorsal fin and fluke. Place this beside your working area to help you sculpt the whale.
Knead the clay like bread dough to make it consistent and workable. Form the basic shape of the whale. Taper the shape outward from the thickest region in the middle of the whale. Keep enough clay near the tail end so that you can form the fluke. Leave a little extra clay on the sides to form the flippers as well.
Form the head of the whale with your hands and pinch the sides to begin forming the flippers. Use your fingers and a wet sponge to form the fluke. Use a close-up reference image to detail the shape of the fluke and head. Pinch the top of the whale to create the small dorsal fin. Form the body in a way that it looks alive and swimming.
Place the formed whale on a soft 2-inch by 2-inch block to suspend it from the table. Form the two typically long humpback whale flippers and let them hang down the sides of the block to make the whale look like it is in the water. Use a knife to create the small breathing holes on top of the head.
Detail the head, eyes, flippers, dorsal fin and fluke until each looks as real as you can make it. Mix a small amount of clay with water to create a wet mud. Use a toothpick and place small drops of the mix on the whales head to simulate barnacles. Carefully mark the curved line of the mouth using a knife. Create the rugged front edge of the flippers with the knife.
Clean any finger marks using a sponge, and soften areas that are too rough. Run the sponge along the body of the whale to give it a very smooth surface. Detail the whale until you are finished with the figure and let dry. Be careful not to break off the flippers.