To make this piece of terrain I glued a couple of sheets of pink foam together to get the thickness. Once it had dried (overnight) I got out the hot-foam cutter and cut out my rough shapes. Once I was happy with the angle and height I just started taking out little bites to get the texture right.
Next up was the most tedious part of making any kind of foam terrain - painting. You can't just spray down your foam terrain with spray paint or it will melt and just make a mess out of it. You end up with all these little holes that you cant just paint over because it in turn makes more little holes.
So I grabbed my terrain paints and a big brush and coated the whole model with a nice brown color. I then went back over the top of that color with a lighter brown. I based the model using the same colors to tie it all together.
This is one of my favorite pieces of terrain. It sticks out on the table and is nice and tall.