Using a tutorial from Cryonetic Studios shown to me by Kyle , it allowed me to get a greater understanding of how to texture using the PBR method. I used gimp and followed the tutorial in order to produce the different maps.
Following the tutorial he first creates an albedo so I imported my rock texture and went through the steps. In order to get an albedo map you have to desaturate, then invert and change the levels. To change the levels however you need to get a reference chart which which is the image below in order to find the medium number on the histogram chart.
The next step is the gloss map. Here I desaturated the lightness and then used the levels again by finding the medium.
Here is the gloss map
After this is specular which requires you to desaturate the luminosity and then levels again.
The last step is creating the normal map which you create by using your albedo map, then using the normal filter in order to produce this. You can change the scale if you want the detail to be thicker and clearer.
Creating a normal map
After this I put it all into unreal in order to create a material as you can see here
Once the maps are in the correct places I assigned it to a simple floor I made within 3ds max.
This was my first try at creating a pbr texture and it is clear to me that more practice is needed in order to get the texture looking better, in the future I am going to carry on this method in order to become more efficient at the process. I am also going to take a look at the software called bitmap to material made by allegorithmic which should speed up the process considerably.