Hello!
For starters, welcome! Hopefully you have a need for a different intersection or otherwise and this will provide! Some basic things to keep in mind:
-Pre-Signals are RELAYS! They display the same signal as the signals in front. One presignal before one signal that is occupied? Red light. One presignal before two signals with one occupied? Yellow light.
-Your Pre-signals are how you route your trains. They will hold a train short of the intersection, if that is planned, until a route into and out of the intersection is open
-Pre-signal INTO the intersection regular Signal OUT
-Made an intersection, then an exit right after and having trains stop in the intersection? Expand your signals to include this exit in the Pre-signal/signal network.
-SEPARATE your rails into blocks! This is actually what signals are doing and you need to block your rails out in accordance to the lengths of your trains. Too long of a train going into an intersection it may block the intersection even if the engine is in the exit.

-This guide is going to be built overtime! I will add to, remove, or expand upon concepts as time continues.

This section will be ALL about your intersections into and out of a train station. This can include RORO (Roll on Roll off) stations where train enters and leaves in a straight line. It can also be, if you play with train flipping, train enters and leaves same direction. Or whatever craziness people have come up with!

Keep in mind: There are several ways to do a train station. There isnt a wrong way so long as trains are able to move in and out freely. How you design your overall network is going to dictate in what way you connect your stations.

Basics:

This is a, as im going to start calling it, a Roll In Roll Back station. Signal placement here prevents trains on our lower rail, the light blue, from entering unless the intersection ITSELF(Red) is clear as well as atleast one lane on the station. If no lane are open, they hold short. Signals on exiting prevent entry into the intersection, again the RED block, until a train has entered the light green exit rail. This station is useful as an end of the line station. As in, you are not intending on trains traveling through this station or around to another area.

(Another example, notice how the rail connections to the station are different. The way the rails themselves matter little compared to proper signalling)


Our first RORO station! Similar to our previous station, signals turn the station into a block, and the two interchanges on the entrance and exit into blocks. Signals on the exit prevent them leaving until the first interchange is cleared. You can play with signal placement based on train length if needed. This station has the advantage that trains do not need to turn around. The animation does take some time to occur, whether that time is a big deal is up to you. This station also has the advantage of not being an end point. You can branch off the exiting line to go where ever you need!

What is this monstrosity? Well it is a roundabout! They work EXTREMELY well for train travel







Roundabouts work so well in this game, if i have issues making an interchange for multiple lines ill most likely put one down. Signalling is not difficult for these either.


This is that same roundabout showing signal placement. Pre-signal INTO the intersections Signal OUT of them. Use signals on the long sections to split if needed. The idea is that a train does not enter unless the next long segment is open. Lots of trains may cause them to slowly scoot around so be careful on your sizing. Each side should be close to the same size if you can.