Newman Atkinson says:

There are several ways I an making connections. A lot of it depends on how often I would be disconnecting them. I have built my layout so that if I move, That the layout will come apart to do so. For the occasional disconnect like I might need to get service men into the furnace I am using the terminal strip block. I also have 2 sections that are removable to get things through the overhead door if needed. I also have modular sections like portable clubs use that I use the four prong trailer connecters for a quick connection. These work very well for any position but have gone up in price over the last several years. These modules I set up in the other bay of the garage for extra track-age when I have a large group over to run trains These will link up to the main layout with a bridge board. I also use this connecter to quickly hook up the transformers on my portable layout that I take to shows for a very quick connection. (If you use these, and you have enough wires to follow(like switch yard tracks then to protect getting the connectors onto the wrong set of wires make sure you reverse the direction of the second connectors so they don’t get confused. On the main layout I have a pair of 16 gauge trailer wire parallel the tracks underneath and I use short phone wire for a wire drop and I use these every 4 to 8 feet to ensure good power. I also use different colored wires to ensure I am following the right wire fore that track rail. I still solder the wire drops to the buss wires below but any of the suggestions mentioned above will work.
I use the screw terminal strips where each section of board might need to break apart at some point. I also use these screw terminal strips to connect items with multiple wires like signal lights and switch machines. Tortoise switch machines are an example where they are using 8 wires that needto be kept neat. The wire hook-ups to keep the wires organized.
As far as insulating the wired connections, I do it several ways. Depending on the connection, I will use the heat shrink tubing. Where there are multiple wires in the connection I will use electrical tape. I especially do that if I plan on adding a few more wires in the near future or if it is a temporary connection. And for connections that are hard to get insulated I have been using the liquid insulation and that has been working very well. Just remember to Keep the wires insulated, follow a color code to keep from mixing up your wires (all one color of wires will surely get mixed up at some point), and especially at the connection terminals follow the same wires across the terminal block so they are always in the same order. In other words: for two sets of tracks I will have four wires. I personally use a red, green Yellow, and black. I keep them in the same order across the terminal block and hopefully in the same direction and same order of the rails I am following. Happy Railroading!
from Newman Atkinson