How to ship birds when i sell them?

I Live in the city, i have some chickens but if i want to trade one or lets say sell them. How would send them trough usps.
I Know i need a poultry box but what do i say to them because im thinking they will look at me like im retarded. Again is the city. so what do you guys do when shipping birds and i guess this question pertains to people who live in the city as i do.

Also as part of this question lets say im shipping to texas or cali or some state way west which im thinking it would take a couple of days. How do you prepared the birds and what do you put inside the poultry box for bedding, food and water source?

Thank you in advance!