►► This technique makes use of Photoshop’s Photographic Toning gradients. If you don’t have them loaded in already, go to Window > Gradients, then click the flyout menu in the top-right of the panel and choose Legacy Gradients. Next, add a Gradient Map Adjustment Layer. Open the Photographic Toning set in the Legacy gradients, then experiment with the range of vintage toning presets available.