You don't specify the time period in which this takes place, but prior to the Staggers Act of 1980 the procedure remained essentially unchanged for decades, since everything was specified down to minute details by the Interstate Commerce Commission (ICC), down to the size of typefaces used in printed tariffs. All rates had to be published in tariffs filed by the railroad with the ICC, and whatever was in the tariff governed absolutely, to the point that if a shipper made an error in reading a tariff and misunderstood what the legal rate was, or even if a railroad rate clerk slipped up and misquoted a rate to a shipper, the tariff nevertheless prevailed. The ICC prescribed a document, the most common being designated the Uniform Straight Bill of Lading, in 3 copies: the top designated the Bill of Lading, the 2nd copy the Shipping Order, and the third Memorandum. There were blocks (called "fields" today) for Destination (which had to be a station shown in a tariff), Consignee, Route (the shipper had the right to specify which railroads would participate in the route, provided it was one of the routes specified in the tariff), plus other information such as the party to be notified at destination, and various other arrangements or services, always provided that they were permitted by tariff. All this was on the left half of the document, everything on the right pertaining to origin -- specifically, Origin station, Shipper, and I forget what all else. The shipper would type all this out, using carbon paper (!) and either deliver it to the local freight agent, or, frequently, phone the agent that he had a shipment ready, and the agent would drive over and pick it up. Both the shipper and the freight agent would sign the document, and the shipper would retain the Bill of Lading and Memorandum copies, while the agent kept the Shipping Order, which became the foundation for the waybill, typed out by a clerk in the freight station and handed to the conductor of the local freight which picked up the car. Normally the waybill traveled with the car in the possession of the conductor of each train the car moved in. (Nowadays this is all done by electronic data exchange in which the shipper inputs the movement information directly into the origin railroad's computer, and the conditions, rather than being published in a tariff, are whatever the shipper and the railroad have agreed on.)
All this is probably more than you need, but the main thing is that the whole procedure was standardized, and everybody, railroads and shippers, knew the rules -- they had to. The execution of the bill of lading was actually the last step in originating a shipment. The first step was for the shipper to phone the local freight agent and order an empty car placed on his siding (or, as mentioned in an earlier post, a team track, the location of the team track being specified in the tariff by name, usually the name of the station). The shipper would need to specify the type of car needed, as well as the destination of the shipment and the route, because the ICC periodically issued car service orders specifying what cars of what (railroad) ownership could be loaded to which areas via which railroads. The agent would then call the railroad's car distributor, who would locate a car of the type and ownership needed, and issue instructions for that car to be placed on the siding or team track specified by the shipper. In more recent years, local freight agents largely disappeared, and shippers would deal directly with the car distributor. Much of this activity is now handled entirely by computer, including identification of a suitable empty car and issuance of necessary movement instructions, but the functions are essentially the same. If the shipper has any questions nowadays he e-mails his contact at the railroad, who may be on the other side of the country.
