Howdy back,
Glad to hear that someone noticed!
I use a GoPro Black 8 camera, can mount it to a tripod, set between tracks on benchwork or mount to a car that I push past the "action". I also use my android phone for still photos on the layout and outside (I like our natural environment and show it as much as possible).
I use HD Movie maker Pro, a program bought in the Microsoft app store, I think it was $10, don't bother with the free ones.
The program lets me add and edit video and still photo clips, has neat transitions, text-overlay feature, other features like slo-motion that I still need to explore. Also can record sounds to my phone, add separate to the video, sound can be edited. You tube has an audio library with more free music than you would think. Occasionally I am required to give credit on the last clip.
It is a lot of work, moving trains and lights around and setting-up the camera. The Gopro has a wide field of vision, so it can be difficult to keep undesirable elements, like MYSELF out of the scene. I do have an occasional helper, but do most myself. Please ask anytime, if I can answer any questions. Jim