When reading a textbook for school while at work with a title like Marital and Sexual Lifestyles in the United States be sure to flip it over and face the spine away from customers. One customer this morning asked if it was a good book and then told me what his wife recommends. It's a textbook, I promise!
When you are away from home, be it in public or in another person's home, and once you are over the age of 10 and you need to use the bathroom: Politely ask, "May I use your bathroom?" There is no need to grab yourself for added effect. Also, women would much prefer you leave the seat up than to sprinkle all over the seat.