Whether you’re trying to look good for a date or just have something from dinner stuck in your teeth, there’s never an appropriate time to groom yourself in public, and it’s a habit you should break as soon as possible. “Any personal grooming should be done in the bathroom. There are these things in there called mirrors, and they should be used,” says Thomas. “That goes for putting on lipstick, flossing, brushing hair, or using a toothpick.”