Stone carving has not really changed over the millennia. We still use hammers, chisels, saws, and files to shape the stone. The only difference is that today many tools are powered by air or electricity. Power tools allow me to work faster, but I use hand tools for a lot of the work it is far more satisfying and gives a deeper sense of connection with the stone.
Stone sculpting is subtractive, a one-way process. Once a piece is cut off (or falls off!) there is no putting it back. So, a lot time is spent thinking and visualizing before so any cutting or chiseling.
But with every piece there is Whoops moment - something falls off or breaks differently than expected. It took me along time to recognize these moments as good, as the intervention of the stone itself guiding the evolution of the work. In every case, the Whoops resulted in a better, more interesting and creative piece.