Cut the hill shapes and put them on the board. I like to move them around and see if they fit how I envisioned, before moving onto the next step.
Using wood glue, glue the hill sections together and let them dry over night.
Use a sanding block to “rough” up all the surfaces.
At this point I decide that I want to have permanent tiles on my terrain board. These tiles need to look like they are hundreds of years old and long forgotten.
Coat all surfaces with a 1:1 mixture of wood glue and water. Then sprinkle the surfaces with sand. I am using “play” sand from the hardware shop.
I have also craved a few tiles on one of the large hills (bottom left of picture).