Train aggregate loading
Train aggregate unloading station with connected large aggregate storage
In addition, you must also build a train depot, otherwise you will not be able to buy trains.
Now you should have all the buildings needed for the transport of coal. Next you can turn to the construction of the railways. Here I recommend you to build two tracks parallel to each other wherever possible. At this point you should decide if you want to have electric or diesel trains, because for electric trains you need to connect your railways to your power grid and for diesel trains you need to build a diesel station for trains.
Once you have finished building the railways, you should cross the railways in front of the train aggregate loading and train aggregate unloading stations. This has the advantage that both tracks of the loading and unloading stations can be used by several trains.
Once you have built the rail cross, do not forget to set up the signals. Here, when entering a crossing, a Cain signal should be set up in the direction of the crossing. Since chain signals connect to the next following signal and thus get not only the status of the next track section but also the status of the following track section, you can thus ensure at crossings that trains do not block the crossing.
For the rest it is best to use the normal signals.
Note that the railways leading to or from the train aggregate loading or train aggregate unloading stations require signals with double arrows, since these track sections are used in both directions.
Now connect your train depot to your railway network.
In this example I have chosen a T-crossing to clarify the signals once again.
When placing the signals, please note that a chain signal should be placed everywhere where a train can enter the rail crossing. This way the crossings remain clear even if several trains are running on the track.
In order to clarify the chain signals whats again, I'll give you the following example.
A train stands in front of a chain signal (1.). The chain signal not only makes sure that the track section (2.) is free, but also that the next track section (3.) is not occupied by another train. Thus you can use chain signals to keep crossing areas free.
You should divide the rest of the track into several sections with simple signals, because a section can only be used by one train at a time.
In the picture, each line represents a section of track.
I hope I could help you a little bit with creating train connections in Workers & Resources: Soviet Republic. Feel free to leave me a comment if you liked my guide or if I forgot something.