The waterways shown in every photo was made using an acrylic product called Mod Podge. In all examples the base was either hardboard, foam core or Gator Board.
I paint the base using cerulean blue, medium green, black and white. When dry a dozen thin coats of Mod Podge is plopped on. It's not brushed on - brushing produces bubbles - just use a soft brush and lay it on.
As you can see one set of techniques can produce various results.
