Good oral hygiene is one of the most important things you can do for your mouth to avoid cavities. Regularly brushing and flossing keeps dental plaque from forming and eliminates the food source of bacteria strains like streptococcus mutans. The American Dental Association recommends brushing twice a day and flossing once, but timing can also be important. Because plaque forms within 24 to 48 hours, brushing before you go to bed and when you wake up can cover your bases while you’re asleep. This is especially important because production of saliva--the body's natural antibiotic--drops off at night, making it easier for bacteria to multiply.
For those who are adverse to floss, that’s something you’ll have to get over. Unfortunately, a toothbrush can’t reach all the places tends to hide. Using floss can help you to clean those hard to reach places, like under the gumline. But there are alternatives, too, like water flossers and interdental brushes, that might work better for some people.