If you want to follow along and paint, here is a list of supplies I used:
-- Grubby old brush -- a little larger (Size 3 or 4)
-- (paints) Black
-- P3 Bootstrap Leather (or just a dark to medium brown)
-- Foundry Base Sand (or any light tan/beige color)
-- Foundry Raw Linen (any off white; raw linen has a touch of yellow/green to it.)
-- water, paper towel, mini!
One last note: I went just a touch heavy with the paint here -- it's just a matter of wiping off a little more excess. The effect still works, it just takes a little longer to dry.