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How to tamp concrete
Build a formwork for your concrete surface.
Before you begin tamping or even pouring the concrete, you'll need to have forms in place. Nail together a series of boards to fit the area you'll be concreting, dividing the different sections as needed.
Use a level to make sure the surface comes out perfectly flat. Formwork structures serve to mark the perimeter of the concrete surface and contain the wet concrete mix while it's being spread and compacted.