Spoons can be used to deliver small rounded shapes to a form or to remove small wells in a shape. Flat sticks, spatulas or table knives can be used for sharp edges, angles, or flat shapes. Yogurt containers packed with sand create symmetrical flattened cones for the tops of towers or border designs. Paper cone cups are great for the roofs of turrets. Round bottom bowls create domes, plastic scrub brushes create texture, and chopsticks can be used to reinforce a tall slender shape.
Sifters can be helpful to remove any miscellaneous debris, especially for fine detail work.
Don't forget found objects to decorate your creations. If you are at the beach, seaweed, shells and sand dollars make great add-ons. Remember that the shape will be reduced as you carve, so start with a large amount of wet sand and begin cutting it away. You can add more wet sand, reshape areas, add or remove texture and add pillars or surface decorations. The sky is the limit.