Cold and flu season is upon us. Your biggest weapon in the fight against germs? Keeping hands clean. Everyone should wash up before eating; after using the bathroom; playing outside; handling pets; and whenever hands look grimy -- in other words, all the time. The biggest mistake (grown-ups are guilty too) is not washing thoroughly. Use liquid soap and rub hands for 20 seconds, about as much time as it takes to sing the Happy Birthday song twice or the ABC song once. Then don't forget to dry hands completely!