What you are asking is beyond the scope of a simple explanation. Ideally you need to learn to use the cycles nodes and understand how to mix shading values of different types using masks as factor inputs. The masks themselves can also be complex procedural nodes using various types logic to generate the effect. There are many different techniques that could be used.
If you are not prepared to learn any of that - then you just need to search the internet and blender related websites to find an already created node set up with or without textures required for masking effects and just copy it.
I would highly recommend learning to use the node system. There are some good learning videos for this on blenderguru as well as a ton of other videos and resources to learn how it works.
If I were you I'd download the Substance Painter 30 day trial and go through all of their tutorial videos. Or at least just watch a few of the videos to get an idea. I'm sure there is other software for doing this (I use painter) but personally these days I do not think something like Photoshop is it. Took me stumbling across painter to realise.