Please accept my apologies in not answering you earlier.
As a retired electrical engineer, my hints and tips are electrically based.
When wiring your layout, buy a reel of alarm cable. A 100 metre drum of 8 core alarm cable will cost under £20.00 plus v.a.t. This will give you 800 metres of cable for £20.00 which is the equivalent of 25p per metre.
Sleeving is a thin walled pliable plastic tube which comes in red, brown, blue, black, grey and green/yellow. 3mm diameter should be adequate for most needs, and costs around £5.00 for 100 metres. Push your cables through this sleeving. Use one sleeving colour for each function, e.g. red for track supplies, green/yellow for signalling, grey for points.
Use one colour per function which will make fault finding easier. E.g. when wiring points, I use green for the main line, red for the diversionary route and blue for the common return.
The alarm cable and sleeving may seem a large outlay, but when you compare the equivalent cost typically over £3 for 7 metres with buying 800 metres of connecting wire in small packets, the outlay is not so great.
Make a circuit diagram of your wiring.
Test each circuit and remedy any faults before going on to the next.
Some of you may remember John’s pics of his first layout (if you don’t, they are here).
Well, he’s been kind enough to take some video of it:
Big thanks to Cedric and John. Please keep ’em coming.