Keep It Closed and Dry Inside: It is customary to close your umbrella before entering a building. Remove any excess water by gently taping the tip of the umbrella in front of the building a couple of times. The first question upon entering should be where you may place the wet umbrella to avoid further dripping. Make use of the carrying case that came with your umbrella, or the disposable plastic bags that many office buildings and stores provide, to cover your wet umbrella while indoors.
Park Umbrellas with Care: Be mindful of where you place your umbrella. If no umbrella stand is provided, set your umbrella upright with the tip on the floor beside you. In trains, planes, and automobiles, lay it on the floor near your feet, not on an empty seat where other people may sit on it or the puddle it leaves behind. Keep your umbrella away from walkways where someone might trip over it.
BONUS: Prevent Umbrella Loss: Folks at any lost-and-found department will tell you they have hundreds of unclaimed umbrellas in storage. If you forget your umbrella somewhere, you may have a chance of someone returning it if you tape your telephone number and/or email address to the very top of the umbrella’s main strut above the handle, where it will least likely get wet and come loose.
During the next day's rain storm, my wife was coming out of a different grocery store. (We grocery shop a lot.) As she was being pelted by rain, four people walked by with their umbrellas, passing her in the rain. My wife did not have an umbrella. Poor planning? Perhaps. But I have spent time on many a rainy afternoon holding my umbrella over a fellow patron who was trying to unload groceries without becoming a frog. "Chivalry," my wife said, "is extra dead." I mean, is it so hard to be aware of your fellow citizen that you can't stop for two seconds and say, "Gee, perhaps she would not want the rain pelting her as she loads bags into the minivan?"
Don’t hang your umbrella or wet coat right next to someone else’s coat
Do ask for guidance when entering someone’s office regarding proper placement of your wet items
Do tap excess rain off your shoes before proceeding into an office (or home*)