This tutorial/description?
Blockquote How to use grain and watercolor paper textures:
Unzip file with Watercolor Paper mount textures in proper layers.
- Inside “Paper Fill” layer Properties you should load “DA_Pastel_Honeycomb midgrain.png” (this texture is made by Ramon Miranda and was part of his Digital Atelier brushes pack)
- Inside “Grain” layer Properties load “WatercolorGrain.png”
To make this click wit RMB on layer >Properties → click icon of folder → load texture → find proper texture on the list and click it again