Locate your chosen access point for reentry into the United States. This will be either an international airport or a land crossing.
Get in an open queue at your chosen access point. This will be specific lanes on the road or lines in a U.S. airport terminal.
Prepare your U.S. passport and other identification as you wait for an available customs agent. U.S. passports are all that are required for air travel. Land travel requires a valid driver's license and passport.
Show your U.S. passport (and driver's license if at a land crossing) to the customs and border security personnel.
Answer the customs agents' questions truthfully and do what they tell you to do. U.S. customs officials are permitted under U.S. law to search or detain you if they have probable cause to believe that a criminal act is being committed.
Pass through the customs security checkpoint after being approved by customs and border security personnel. You are now back stateside.
