A couple of gallons of water doesn't seem like a lot. Scrub and clean the bathtub and fill it with water. If the electricity goes out your water supply might not work, even if it's municipal. The water in the toilet tank can be used for quick washes since it's clean. If you have them or can get one or 2, fill a garbage can with water.
Use a wastebasket lined with a plastic grocery bag (with handles). Put some cat litter, newspaper, paper towels in it to use as an emergency toilet. Just put the bags outside until they can be sent to the trash.
Play cards to pass the time. Good luck