Even if you master the focus and composition of a photograph, it might come off as a bit too calm for certain uses. The Digital Photography School site explains how to apply interesting image textures to any photograph.
In the example shown at the DPS blog, the rough and slightly yellowed look of a scanned piece of paper is applied as a layer to an over-the-shoulder portrait, giving it a look and colour tone that matches the look the model is giving off. For beginning Photoshop users, it's a great entryway into the art of applying just the right look to photos that lack for the right mood. Hit the link for the full step-by-step run-down, and tell us about your great texturing results in the comments.
How to Use Textures to Enhance Your Photographs [Digital Photography School]