As a footwear designer, photoshop rendering of a concept is the best and easiest presentation material when explaining a design to team. In order to visually introduce every detail in a product, applying material texture, pattern, etc. is an essential practice when achieving photo realistic effects in a product. I have put these resources into category for easy access. Each category has some of the most used and common texture, pattern swatches. Just click on each image to display a large version.
Enjoy! And be creative!