When entering a Japanese house you should always take off your shoes at the entrance and change into some slippers (or surippa), the host will usually have them ready for you. But don’t go stepping on a tatami floor with them, the tatami mat is only to be walked on with socks or bare feet.
When visiting the toilet don’t forget your toilet slippers, as you can’t wear any old slippers in there, you never know what you might stand in. You should leave you house slippers at the washroom door and put on a pair of toilet slippers that you will usually find just inside the door.
Slippers are used in many places other than the house in Japan, if you visit a Ryokan you will be supplied slippers to wear. Many traditional style restaurants ask their clients to pop on some slippers before entering for their meal. You may also come across some museums, galleries and temples that also have the slipper rule. Many school children also wear slippers to class.
Most western style hotels, often known as business hotels, will also have slippers and a robe in the room. These are provided more for the convenience of the Japanese guest, and you don’t have to worry about wearing your shoes inside a western style hotel, but if you want to live it up like Bill Murray in Lost in Translation you should give them a go.
There’s no real need to panic, not knowing when to pop your slippers on and when not to, as most of the areas have raised or lowered areas where they are needed, and there is always a row of shoes and spare slippers for guests. The shoes should stay on the first step (or on shelves if provided) and try not to step on the first step (the genkan) with your bare feet or socks as it is considered not polite. Also, be extremely careful not to leave your toilet slippers on when re-entering the house.
The slipper custom might seem a bit strange, but it’s a exceptionally good way of keeping the house clean especially with all the woven items and polish woods found in many Japanese homes, and lets face it the slippers are much more comfortable than your work boots. The idea behind the custom comes from how the Japanese traditionally perceived their homes with the outside being unclean and inside being clean. It is this reason you should never contaminate the outside or toilet area across onto the inside living areas.
Some western people might find the slippers supplied are a bit too small, so you might want to purchase a cheap pair at a discount store if you plan to visit anyone’s house, just remember you might need to take a second pair for the toilet.