How to Colorize in Photoshop
Create a Selection of the Area You Want to Colorize
In order to colorize a specific area of a photo, first, you will need to create a selection around that area. In this example, we use “Select-Color Range’ to select out the pink hair.
After making the selection it needs to be refined. To refine the selection even more, hold ALT/OPTN and click on the layer mask of the Hue/Saturation Adjustment Layer and paint white or black with the Brush Tool set to ‘Overlay’ Blend Mode.
Hue/Saturation + Colorize
How to Use Two Layer Masks on One Layer
In this example, we work hard to create a great selection around the Hair of the subject. Because we want to colorize different parts of the Hair, it makes sense to keep the original Layer Mask intact.
To keep the original Layer Mask intact and hide additional parts of a layer, try grouping a layer with itself and adding a layer mask to that group. This is a way to effectively have two Layer Masks controlling the visibility of one layer.