Building a layout

[Anonymous]

I have operated O GAUGE trains on & off for about 20 years. In that time I have built 8 or 9 layouts but only on 1 layer.
What I need is some detailed & exploded drawings on building multi-layer layouts. I do not have unlimited space, but I do have a 15 X 12 space available. In addition to exploded drawings, a materials list would be handy. I can build, I just can't design.

Alex Turner