Use the best slab cutting machine for the job. There are several types of hand-held saws (wet or dry) that are good for most concrete cutting applications. For a large job on the floor, consider using a walk-behind saw. These heavy saws make the straightest and deepest cuts, eliminating the need for repeated shallow cuts. Walk-behind saws are wet saws. Water keeps the dust down and also keeps those big blades cool. With hand-held saws, wet vs. dry is partly a matter of personal preference. Wet saw creates a messy slurry, but they do keep the dust down.
Select the right blade. In most cases, a diamond saw blade is the way to go. The exposed synthetic diamond crystals on the surface of the blade do the cutting. As the diamonds become dull, they fall away, and new ones are exposed. You can use a dry-cutting diamond blade with or without water. A wet blade must be used with water.
Deal appropriately with the dust. This especially critical for professionals due to the new OSHA respirable crystalline silica standards. If you’re using a dry saw, make sure it has the appropriate dust extractor. (With a wet saw the dust is washed away before it becomes airborne.)