Japanese etiquette 3 - slippers

The slipper etiquette is not difficult, if you're a physicist. Let me begin with the underlying principles:

• The goal is to keep clean areas clean. In rank of dirty to cleaner, we have: 1) Outside and the toilet, 2) the main home, 3) the bathroom (where one takes baths)
• Whenever there is a change of level between areas, that's a signal for a change of footwear. The cleaner area is at a higher level than the dirty area. This brilliant technique avoids the tracking of dirt into the clean area.

And that's all a physicist needs to master the slipper etiquette. For the rest of us, let me spell it out some more. 

1) When you step into a home, take off your shoes. In a traditional home, you will see a change of level, with the living quarters floor being elevated compared to the entrance. You may or may not be offered a pair of slippers. Step on the higher floor only after you took off your shoes. Try this at home too. Keeping your floor clean will become a lot easier and carpets will last longer.

2) If you open the restroom door and find a pair of slippers waiting, change into them before using the restroom and don't forget to change out of them when stepping out (that's the hardest part).
3) In the bathing area, you need to go in barefoot.

Rubber slippers to change into when going into the restroom

Some additional tips for your own comfort while in Japan. If your feet are unusually large (as they probably are if you are a man) or unusually small (a US size 5, sadly, is small even in Japan), consider bringing your own slippers. It's hard to walk with slippers that won't stay on your feet and I won't mention the inverse, embarrassing predicament.