If the idea of describing how to use a Japanese toilet sounds like a strange topic to discuss, then I would agree. However, it is also something that has the potential to cause a lot of confusion for the people of the world who do not understand Japanese characters, ie – Kanji (漢字), especially common on a Japanese toilet.
When using a typical Japanese toilet you will see a variety of buttons which perform various functions. Obviously, the most important 2 buttons you will need to know the difference between is 小 and 大, which simply mean small and big respectively. So in the context of flushing a Japanese toilet, use the 小 for a small or half-flush and use the 大 for a large or full flush.
The other typical Kanji you will see on an electronic Japanese toilet is just the general button/switch for flush which is represented by 流す (Nagasu), which essentially means ‘flush’. I have also provided other diagrams to explain some of the other functions, should you be fortunate enough to encounter some of the more complex systems. Ganbatte (Good Luck)!