You stick your hands in it all the time. So do your kids. But you rarely clean it. That accounts for the bacteria that live inside it. The places you leave it, like dirty counters, bathroom stalls, and car floorboards, account for icky travelers on the outside. Hang it on a hook when you can, and clean it with antibacterial wipes. Think about the outside, too -- pebbly or uneven surfaces can make better homes for bugs than smooth ones.