Though bleach effectively sanitizes concrete floors, working with bleach can lift the dye from fibers and stain your clothes. Even if you're careful, there is always a chance some of the bleach might splash onto your clothing or shoes. So you need to dress accordingly. You also need to ventilate the area properly to avoid breathing in bleach fumes. Open a few windows or bring in an electric fan to circulate the air.
Sweep or vacuum the floor to remove any loose residue.
Fill a bucket with hot water and add several squirts of liquid detergent to the bucket to make soapy water.
Mop the floor with the soapy water, and rinse thoroughly and allow the surface to dry completely before moving to the next step. Any detergent left on the floor can inhibit the bleach’s ability to sanitize the surface.
Fill a clean bucket with hot water and add liquid household bleach. Use about 1/2 cup of bleach for each gallon of water.
Mop the floor with the bleach solution, using a clean mop. Allow the solution to set for 10 minutes.
Rinse off the solution using fresh hot water and a clean mop. Allow the floor to dry.