First, brush and floss as you normally do.
Place one or two drops of the dental disclosing solution in your mouth and allow it to mix with your saliva.
Swish the mixture in your mouth for about 30 seconds. Run some water in your sink, then spit out the solution into the running water. (Running the water helps ensure that you don't stain your sink).
Gently rinse your mouth with a small amount of water and spit again.
Then, examine your teeth for plaque colored by the dye. Because the dye stains all bacteria, your tongue and gums also may get stained. Anything that is stained contains bacteria, and is considered not properly cleaned. So, the next time you brush your teeth, pay special attention to these areas.