Summarize:

Water-based stone stains come in a variety of colors. Before selecting a color, look at several and decide which will be most complementary to the shade, type, and texture of stone in your home. You can buy water-based stone stain and sealant at your local hardware or home and garden supply store. Make sure that the type of stain you select clearly states that it's made for use on stone. Never apply wood stain to stone. If you're covering a large area of stoneworkand especially if the stone is outdoorsit's most efficient to put the stone stain into a plastic spray bottle. Use a funnel if needed, to avoid spilling stain. You can usually purchase these at any kind of grocery store, drug store, or dollar store. Spray a thick, even coating of the stain over about 1 foot (30cm) of the stone at a time. Or, if your stonework comprises large stones with mortar between each, spray 1 stone at a time. Be sure to spray the mortar between the stones with stain, too. If it's not stained, it will look out of place. The mortar will not be damaged by the stain. Working slowly to cover the entire surface of the stonework will ensure an even coverage and similar color. Work the liquid into the stone with a bristle brush. Move the brush in a circular direction in order to work the stain deeper into the stone. Help the stone maintain a natural look by smoothing out any obvious spray lines from when the spray was applied. Using a bristle brush will also help you make sure that the stain is applied consistently and evenly over all the stones. The stain needs to work into the stone and dry before it's touched or sealed. Give the stone at least 8-10 hours to dry. Once the stain has dried, you're ready to move on and seal it. In general, a single coat of stain is enough to visibly alter the color of each section of stone. However, if you'd like a darker, more pronounced color, apply a second coat using the same techniques that you used for the first coat. When moving from section to section of the stone, try to overlap the stain by about 1 inch (2.5cm) so that the lines between sections are not visible.
Select a color of stone stain. Pour the stone stain into a plastic spray bottle. Spray a small area of stone at a time. Use a bristle brush to work the stain into the stone. Let the stain dry overnight. Apply a second coat if you'd like a darker color.