There are various types of tongue cleaners: the most effective seems to one having the form of a loop. Extend the tongue as far as possible out of your mouth. Breathe calmly through your nose.
Place the tongue cleaner as far back as possible on the tongue, and press lightly with it so that the tongue becomes flattened. Ensure full contact of the tongue cleaner with the tongue. Pull the tongue cleaner slowly forward.
Clean the middle part of the tongue, first using the raised edge on one side of the instrument. Use the smooth surface of the tongue cleaner on the sides of the tongue. Repeat these scraping movements a number of times. Rinse the mouth several times.