You will want the option of privacy and, especially, a clean bathroom. Set up your space, and stock up on basically everything you would need for a few days of a stomach flu plus a gnarly period: saltines and Gatorade for nausea, extra pads (you can’t use tampons or a cup), dark...
It comes in a couple of different varieties. You can buy it in concentrate, which ought to be mixed with milk or water before drinking. Calpis Water is pre-mixed. Calpis Soda is a carbonated version of the beverage. The concentrated version gives you more control over how sweet and sugary...