Toilet Instructions: How to do it
Although once you are behind the closed door you can do whatever you like, you may still find that knowing the local customs can be beneficial. In India, it is customary to use your left hand and a bucket of water to clean yourself after 'number twos'. At other times, the right hand is used for most purposes, especially when dealing with food. In most third-world countries the sewerage systems are very primitive, and flushing paper and other products down the drain is not recommended.
In these countries there is often a wastepaper basket for disposing of your toilet paper waste. If you cannot find the handle to flush, you may just need to use the bucket of water in the corner and tip the water down by hand.
In Asian countries plus many places elsewhere in the third world you will mostly come across squat style toilets rather than the western seated type. Getting used to this requires some flexibility and balance, but once mastered it is said to be an effective position to do the job.
You will also come across many different door locking mechanisms, toilet flushing technology, soap dispensers, and water tap controllers. Sometimes they are just trying to be too clever. Putting the water tap handle on the floor to use your foot is very hygienic and looks good, but I am sure many people never work out where it is and end up leaving without washing. It may take you a few minutes to work out how to keep the door closed or to flush away your business, but it is worth the effort to avoid any embarrassment. If you can't get the door to close, you may need to resort to asking a friend to keep watch or to hold it shut.
In Australia, New Zealand, and a few other countries (and hopefully many more soon), many toilets will have a duel flush system, so that you have a choice of either a half flush if you have just done a pee, or a full flush. This has been shown to save a significant amount of water, and is particularly important where water is scarce or expensive.
Paying for it
In many cities the public restroom cost you to enter. Some people believe that relieving yourself is a natural thing and should not be something you pay for. However, the small cost helps to pay for the cleaning and supply of paper and soap, so long as it is only a few cents you should be happy to pay for the convenience. In some places, such as the Cafes in France, the facilities are for customers only, and you may need to buy a drink before you can use their restroom.
Bring Your Own
In some countries you will have to make sure you carry your own toilet paper as occasionally it may not be available. It is good practice anyway so you don't get caught short anywhere in the world. It is also a good idea to have something to wash your hands afterwards. You can get 'wet towelette' or similar products, and there are also some good liquid gel anti-septic hand cleaners now available that can clean your hands with no water.