When travelling through Cuba, make sure to have small change for stopping at restaurants, hotels, paladares, ranchons (roadside stops), etc., to use the restroom. Often there will be a bathroom attendant who keeps things in order and who provides toilet paper as part of a small fee (usually .25 or .50 CUCs) to enter.
Alternatively, it's smart to carry a small pack of tissue with you when you're exploring further outside cities and into the country. Toilets don't always come with a paper roll, so if you find yourself in a bind, a little extra tissue can be a lifesaver.
Image Source: POPSUGAR Photography / Hilary White