DIY Concrete Cleaner You'll make a paste of 3 parts baking soda and 2 parts bleach. It will be thick and soupy (is that a contradiction? Nah...like pea soup, no?). Grab some rubber gloves and a scrub brush. I made my paste in a shallow glass pie plate (I wasn't sure how bleach & baking soda would react with metal, so I opted for glass to be safe).