Remove surface dirt with hot water and a towel or mop. We recommend you boiling water in a pot or kettle.
Mix together ½ cup baking soda, ¼ cup hydrogen peroxide, 1 tsp dish soap. Shake it well until the solution becomes very foamy and thick.
Pour the cleaning solution in a zip lock bag and seal it. Cut out 1 corner of the zip lock bag roughly the size of your pinky nail.
Apply the solution onto the grout lines and let it sit for a minimum of 5-10 minutes.
Scrub the grout lines with a brush.
Finally mop or Wipe clean.
Once you have completed this process and some areas are still stained which may happen. Simply apply a drop of Clorox toilet bowl cleaner with bleach on the area and let sit for 5 minutes then scrub it and wash it off.