“Use your architect mind,” says Sudarsan Pattnaik, an award-winning sand sculptor from Puri, a seaside city in India. If you’re building from memory, first envision your castle. For Pattnaik, who is 42, that means well-known Hindu or Muslim sites. “I have made so many Taj Mahals,” he says. Build with fine-grained sand already wetted by an outgoing tide. “Dry sand is too, too difficult,” Pattnaik says. Bring tools: hand shovels, buckets with the bottoms cut off and squirt bottles. Tamp wet sand into your bucket molds, setting one layer and then the next, like bricks. Sculpt architectural details from the top of the mound down. Bring reference photographs if you’re aiming for realism.

As a boy, Pattnaik loved art, but his family was too poor to afford education, or even enough food. At 9, he went to work in the home of a neighbor, where he was reliably fed but labored long hours without pay. One day, he walked to the beach, made a sand castle and had an epiphany: “The beach is a free canvas,” he says. He started making sculptures in the predawn before work. Tourists took notice. Eventually, a newspaper ran an article about him. Now he has participated in more than 60 sand-sculpture competitions and festivals, has traveled all over the world and has held a Guinness World Record; he has been decorated with two honorary doctorates and one of India’s highest civilian awards. He still goes to the beach almost every day to make something that will wash away within hours.

Sand is an ephemeral medium that requires a builder to approach the work with equanimity. You’re surrounded by destructive forces: wind, waves, dogs, tides, Frisbees, time and, of course, the whims of your fellow workers. “If four children are making a sand castle, two are building up and the other two tearing down,” Pattnaik says. Don’t become attached to the outcome, but if you make something beautiful or strange, you will have a public platform. Pattnaik now writes messages alongside his works, like “Say No to Plastic.” For him, a sand castle is no longer enough. “Now the sea is rising,” he says. “Maybe in a few years we cannot find sand to make castles at all.”