The 1 - 2 - 3 of sand sculpture is Sand - Water - Pack.
Whether it’s a small hand-shoveled pile on the beach or a multi-storied behemoth, the principle is the same. Saturate and compact the sand. To achieve substantial height, we fill a series of wooden forms with sand, saturate the sand with water, and compact it using tampers and our feet. Essentially, we build a layer-cake of heavily compacted sand.

Using the lower forms as scaffolding, we remove the top form and sculpt that section. We then repeat the process working from top to bottom.