Bear in mind we’ve just learned thanks to the Anthrax Zombie that the Postal Service photographs every piece of mail that goes thru the system.
That leaves HAM radio and private couriers to shuffle around thumb drives.
Another thing is just using as much cash as you can for day to day purchases. Pull it out of the bank for day to day expenditures. Things like gas, groceries, cloths, eating out, etc. If you buy a book use cash and they don't know what you are reading. If you go some where pay in cash and they won't know your where abouts.
A carrier pigeon could carry a lot of info on a micro SD chip these days.
“That leaves HAM radio “
The NRO has satellites that can receive all HF/VHF/UHF ham radio traffic world wide. The NSA has the recording studios. :)