For Visitors to Both Canada and the United States

1. Know the proper entry requirements and restrictions: For Americans, see here. For Canadians, see here.
2. Obtain adequate travel medical insurance before leaving your country.
3. Document your trip: Know when you crossed the border, how long you were gone, how much money you spent on goods you’re returning with, and DECLARE EVERYTHING.
4. Answer the questions the border agent asks you succinctly and honestly. Don’t embellish and don’t crack jokes. Look the agent in the eyes when you speak.
5. Check out the border wait times before you cross, especially if you can choose between two or more border crossings. For visiting or returning to Canada, see here (and more links here). For visiting or returning to the United States, see here.