No matter what type of plaster you use they are mixed in a similar manner. At the street or in the driveway, there will be a large concrete pump truck "Plaster Rig" that mixes the white portland cement and marble dust and pumps it to the pool. At the pool the plasterers begin to shoot the mix on the pool walls and floor. They walk around with special stilts / peg shoes so they only leave 4 little holes that can be troweled out before they are done. The process is a lot like icing a cake. They use a long trowel stroke to smooth out the finish.