Being invited to a Japanese home is a bit tricky for the short-term traveler, but travelers spending an extended stay in the country have a chance to make Japanese friends and be invited to visit their homes. While being invited to a Japanese home is an exciting opportunity, there are certain rules of etiquette to be aware of. When entering the home, there will be a small hallway at the door. Here, you take off your shoes and position them so they are facing outwards on the floor, or in a cupboard. Look where the other shoes are placed and follow suit. There may be slippers to wear, and they can be worn all around the house except wherever there is a tatami mat, or the bathroom where separate slippers are provided for hygiene.
It is also polite to bring some sort of gift to your host. Food (fruit or cakes) or alcohol are the most customary gifts. The reason for this is since space is limited in Japan, consumable gifts are appreciated. However, if you know that your host really likes or wants something else, then bring that instead. For example, before I visited the home at which my friend was staying, I learned that the host-mother was fascinated by orangutans. So, I brought her a picture book featuring them. While you are in the home, you will probably be offered food and drink. It is polite to be slightly hesitant before accepting. Finally, while it may seem counter-intuitive, do not give an excessive amount of compliments to your host and their home. In Japanese culture it is normal to be embarrassed and deny compliments profusely out of modesty. Of course, you should probably give a few compliments, just don’t go overboard!
And if you are a short-term traveler who is adamant about visiting a home, a couple of options are to find a tour where this is specifically offered or for the truly daring, try Couchsurfing.org, where people post free spots in their homes to sleep at night. The shoes rules still apply, but your hosts will probably be more lenient on the rules like bringing gifts or being hesitant.