Familiarize yourself with the regulations. Most airports have pamphlets provided by the U.S. Customs and Border Protection that inform you of everything you need to know. International flights usually have this information as well. It's best to know everything before you begin in order to expedite the process when you get home. This includes what to bring and what not to bring, such as passports and excessive medication, respectively.
Gather all of the necessary documents and identification necessary for re-entry. Keep them in a secure yet accessible place in order to keep the process moving along swiftly. Passports, declaration forms and receipts are a few examples, although situations may vary in such a way that require you to have more documents, as is the case with those who are traveling with their dogs and need rabies vaccination proof, for example.
Pay attention on the airplane. Flight attendants provide useful information about specifics as to what to do and where to go upon landing. This is especially true for those who are re-entering at an unfamiliar airport. In some cases, for example, the plane is short on declarations forms, and the attendants can inform you where to get new ones on the ground before you go through immigration and customs.
Stay calm when going through immigration and customs. Remember, they are trained to ask you sometimes invasive questions. Know that it is simply a routine part of the process. Even though you have nothing to hide, it's important to not appear thrown off guard or nervous, as it can lead to you being further interrogated, which will delay the process.
