How Do I Do That in Photoshop?

Boost Just One Color?

Click on the HSL/Grayscale icon under the histogram (it’s the fourth one from the left). When the panel appears, click on the Saturation tab (“HSL” stands for Hue, Saturation, and Luminance), then go to the toolbar, at the top of the window, and you’ll see a tool whose icon looks like a small target with a + (plus sign) at the top left (it’s the fifth one from the left). That’s the TAT (Targeted Adjustment Tool). Click on it to activate it, then move it out over the area in your image that has an individual color you want ...