Water-Based and Oil-Based Color Stains
There are several advantages to using water-based color stains. For one thing, they offer a range and intensity of colors that oil-based stains can't begin to offer. For another, they can be used without the need for ventilation, since they produce no dangerous fumes, and cleanup is simple – just soap and water.
To use either type of stain, the first thing to do is to stir the stain thoroughly. In both, the pigment settles in the bottom of the can, so only a thorough stirring will distribute all the pigment throughout the stain.
Always test a stain first on a scrap piece of wood – the final color is never certain until it is applied to the type of surface to be stained. Apply the stain with either a brush or a rag, but a rag gives more control: it allows the stain to be rubbed into the wood instead of laying it on, as would be the case with a brush.
The correct method of application is first to rub the stain into the wood using a circular motion, then to wipe it with the grain to get rid of any marks. Keep in mind that a water-based stain will evaporate more quickly than will an oil-based one.
When working with pine, remember that this type of wood has a tendency to turn blotchy when treated with either type of stain, especially around knots. Therefore it's a good idea to use a wood conditioner first. The conditioner takes only about 15 minutes to dry and will make the wood accept the stain more evenly. Simply apply conditioner, let dry, then stain; let the stain dry for a couple of hours.
Stains add color but don't protect wood, so some type of sealant must be used. Don't use polyurethane, though: it always adds a slight yellow tint. Instead, use a water-based finish, which can be applied with either a brush or an aerosol spray.