Photoshop is full of lots of powerful features, and one of the most useful is the Liquify tool. If you are not quite proficient with it yet, this great video will show you everything you need to know about how to use the Liquify tool.
Coming to you from Aaron Nace with Phlearn, this helpful video will show you how to use the Liquify tool in Photoshop. The Liquify tool is so useful because it allows you to quickly and effectively reshape, resize, and move around elements within a photo. Photoshop has made Liquify even easier to use in the last few years, particularly with the addition of Face-Aware Liquify, but the tool is useful for many things beyond just portraits or working on the face, and as Nace shows, you can use it for something like adding more volume to hair.
One thing to remember is that it is extremely easy to go overboard with the Liquify tool. Remember that less is often more, and be sure to take a minute to step away after you finish an edit so you can come back to it with a fresh set of eyes.