What is the best way to prevent a gum disease?

Floss. Before going to bed after brushing "properly" and use mouth wash after flossing and swish it properly around the mouth flushing in between the teeth. I tell my patients to brush 3x/day and not leave food between the teeth to feed the bacteria that when get accumulated can cause gingivitis and beyond... Yes, i agree with the other doctors- see your dentist regularly and eat healthy!
TB, Floss, Diet. Regular and proper tooth brushing and flossing after all meals and at least rinsing out after snacks. Eat a healthy diet reducing the amounts of refined sugar, sticky starchy foods and routine visits to your dentist for check-ups and cleanings are all necessary components for a health mouth.
Oral hygiene. Brushing properly 2x/day (be sure to clean really well along the gum lines) and flossing along with routine visits to your dentist for check ups to catch things when they are small and prevent major issues, is the best way to prevent gum disease and other dental problems.
Brush and floss. Brush 2+ times a day. Floss at least once a day.