If you live at home: At the residence.
If you are on vacation or a long business trip away from home: At the most frequent residence.
If you have no home: At the place of residence on April 1.
If you live in a group situation such as a shelter or prison: At the group residence.
If you are stationed at a U.S. military barracks: At the barracks.
If you are stationed on or off a U.S. military base, not a barracks: At the most frequent residence.
If you are stationed overseas: At the home address according to military records.
If you are a college student and living with parents: At the parents’ home.
If you are a college student on or near campus: In the on-campus or off-campus housing.
If you are a college student studying overseas: Not counted in the census.
If you are a citizen of a foreign country living in the U.S.: At the U.S. place of residence.
If you are a foreign citizen visiting the U.S.: Not counted in the census.
If you have more than one residence, or are traveling, camping or living in another transitory situation (for example an RV, marina or circus): In the most frequent residence or the residence on April 1.
Source: U.S. Census Bureau