Ordinary concrete can be transformed into a colorful and even luxurious looking surface with faux painting and finishing techniques. In addition to faux painting, indoor concrete can be treated with variety of colorful stains.
Test for Porosity
Make sure your concrete floor is porous and able to receive paint. Paint won't last long on a floor with a coat of sealer. Pour puddles of water on the concrete in a few areas, and let the water remain overnight. If the water soaks into the concrete you probably don't have a sealer. If it floats on the surface, your floor has a sealer and you will have to remove it. You can use gel removers or solvents for removing it. See Resources for more information.
Purpose of the Room and Colors
The faux paint and finish you use will depend somewhat on what the room will be used for. For an entryway, you may want to use a faux brick pattern or faux tile. For a playroom, you may prefer a solid color--a light blue or even red. A family room floor should be painted in colors that create a sense of warmth and relaxation, like a light shade of honey or soft brown.
Do a Test Run
Visit websites such as valsparatlowes.com, and view the colors available in designer shades. You may want to decorate a whole room based on the color of your concrete floor. Go to Lowes or another home improvement store, and ask for a few paint chips or even paint samples to try. They come in 8 oz. cans. Paint the colors on different pieces of wood or tile for a test run. See how the paint looks at different times of the day before making a decision.
Try a faux granite surface for an attractive, textured look that's easy to apply. Review images of different types of granite. Once you have decided on the color granite you want to emulate, buy the paint and apply a primer and a base coat (this is the background color). Pour one of the two other colors into a paint tray. Dip a whisk broom into the paint, removing any drips or excess. Flick the paint off the broom onto the base coat, using a flick of the wrist or a paint stick. Repeat this process with a second or even a third color until the floor is covered. Dip a feather in black paint to create tiny veins and webbing throughout the surface.
Consider applying acrylic stains to your indoor concrete floors. Unlike paint, which creates an opaque surface, acrylic stains are semitransparent and come in nearly every color. Acrylic stains sink into the pores of the concrete, so they won't flake or peel.