Sometimes, your image just isn’t quite vibrant enough. It might be tempting to just increase the saturation, but there are better ways to make your colors brighter. The video below talks through how to adjust vibrance and hue/saturation through a few methods, such as adjustment layers, vibrance adjustment layers, and applying filters. It also discusses ways to target specific elements of an image rather than the overall picture using the quick selection tool. It then guides you through using complimentary colors to make colors pop in already heavily saturated images. Finally, the video will show you how to desaturate other colors in an image to make a particular color stand out more.
These are all great ways to make a slightly dull but otherwise aesthetically pleasing image stand out more by emphasizing or deemphasizing certain colors.