l am afraid that I have not been doing much to the layout as it has been for too cold in the garage!!
I have been building a standard gauge Locomotive and have started some of the scenery at the back of the layout. To cut down on weight I decided lo use expanded polystyrene as the basis for the fields. This is rather mucky to use as it gets everywhere. I tend lo use a sharp carving knife to form the main shape then finish of with a small surform .
The whole lot is then stuck down with PVA. Once it has dried I then paint undiluted PVA over the whole lot and then using a 5O:50 water/glue mix I stick paper towels to the polystyrene. I use the green ones I often found in loos in Hotels (1 won’t say where I got them!) because when they are dry it saves having to paint the ground colour! See below.