Ice sculptors typically use many of the same cutting tools used by a wood or stone carving artist. Power cutting tools, a metal file, ice picks, sanders, burr grinders, and a chainsaw are all tools you might want to add to your toolbox. Consider picking up a book about the art of sculpting ice. "Ice Carving Made Easy" by Joseph Amendola is a comprehensive, easy-to-understand guide.
Find the coldest environment to work in you can. Having a walk-in cooler is the ideal environment, and if you plan to sculpt ice for a living, you might want to consider the expense. In lieu of a cooler, work in the coolest shaded area you have access to. Ice sculptures begin deteriorating almost immediately, so to avoid losing your sculpture's lines while you work, at least keep it in the shade. Using fans can also be helpful. Plan to sculpt quickly if you aren't in an extremely cool environment.
Use special chisels and a rubber mallet for ice carving. These chisels are razor sharp and can slice off chunks of ice quickly. Use a large chisel to remove big chunks of ice. This will allow you to quickly find the rough shape of your sculpture. You can use a chainsaw for the same purpose. Use power sanders to smooth your sculpture. You can also apply a little heat from a blow torch to melt and smooth your sculpture. As soon as you complete the work, take a picture. That will be the only lasting visual representation of your sculpture.