How to Add Powder Color & Hardener to Stamped Concrete

Pour the concrete surface, mixing the concrete in a bucket according to the manufacturer's directions. Allow the concrete cure for 15 to 20 minutes, until it begins to set and forms a plasticized state where the surface is still wet enough to hold an impression.

Spread the powder color and hardener over the surface of the concrete by tossing it across by hand in a wide arc. Cover the concrete with as even a disbursement of powder as possible. Use a small amount of powder to achieve a nearly translucent color, or use a moderate layer of powder for a deeper color.

Wait for the powder to absorb moisture from the concrete, which binds it in place.

Drag a magnesium float across the surface, over the hardener, to drag more moisture to the top of the slab. Wait for the powder to reabsorb the moisture and then dry out slightly.

Seal the hardener into the concrete by going over the surface with a steel trowel. Smooth the hardener with the trowel to work out any clumps and ensure that all of the powder is embedded into the concrete slab. Be careful not to overwork the surface, and go over the slab with the trowel only once--multiple passes can harden the slab too much to allow for stamping.

Use a concrete stamp on the colored concrete while it's still malleable. Place the stamp onto the surface and apply pressure to the stamp until the pattern is molded into the concrete. Peel the stamp up carefully from the concrete to leave a clean impression behind.