Acclaimed facialist Su-Man Hsu shares everything you need to know about how to use a gua sha ‘There are many different Gua Sha tools in the market, and it’s very much a personal choice if you choose one made out of stone, jade, wood’ says Su-Man. ‘As long as it’s smooth and has a round surface, you can use it for Gua Sha as it’s the technique that makes a difference, not the tools.' A Gua Sha tool should always be used on a clean face. Make sure you always use it with your favorite serum or faci