Ensure that the concrete floor is thoroughly clean. Sweep and mop the area completely, scraping any debris from the concrete as necessary with a putty knife.
Clean the floor with a concrete degreaser, following the manufacturer's directions carefully. Typically, mix the degreaser with a specified amount of water and mop the concrete floor with the solution, using a stiff broom to work the liquid into the pores of the concrete. Allow the concrete to dry completely before continuing.
Add color pigment to the concrete lacquer before applying it to the floor. Colors typically come in powdered or liquid form. Make sure you choose one that is appropriate for adding to concrete lacquer, as some pigments are designed to be added to the concrete itself. Follow the manufacturer's directions for adding the pigment to the lacquer, as they differ from one manufacturer to another.
Apply a single coat of the concrete lacquer with a high-quality paint roller, ensuring that the floor is completely covered. However, there shouldn't be puddles of the lacquer on the floor. Allow the lacquer to dry overnight before applying a second coat.
Apply a second coat in the same manner with the paint roller. Allow the lacquer to cure for 12 hours before allowing any traffic on the floor. Ideally, you should wait 48 hours before allowing heavy traffic or replacing items on the floor.