I do many of the things exposed here but I didn't know about the disposable undies. Good tip.
My tip is to bring an umbrella with you. Most of my trips are for pleasure and many times there's rain at least one of the days and sometimes more. That allows me to keep seeing places and not lose that day at least moving from one place to the other. I found another use for the umbrella. Ironically, I was travelling locally and I went to see a festival in Chicago. Sometimes there are problems with the traffic and parking so I travel by train. A friend and I went to the train station to take the train back home. We didn't see any people around. When we opened the door, a man jumped toward us. We ran to the other end of the train station and he followed us. I didn't see him with a gun so I faced him and moved my umbrella like a weapon and with a menacing face and he ran the other way.