Chuck your toothbrush

or change the head of your electric toothbrush at least every two to three months. Otherwise, you're just transferring bacteria to your mouth. According to Beverly Hills dentist Harold Katz, D.D.S., the best way to brush is by placing your toothbrush at a 45-degree angle against your gums and gently moving it in a circular motion, rather than a back-and-forth motion. Grip the toothbrush like a pencil so you won't scrub too hard.