Iv'e seen little amounts of guides on the form so i want to help out.
Tools you will need for Bo2 camo's:
Grayhound: https://github.com/Scobalula/Greyhound/releases/download/1.23.31.0/Greyhound.V.1.23.31.0-release.zip
Paint .net:
https://www.dotpdn.com/downloads/pdn.html
IWI & DDS converter:
https://www.itsmods.com/forum/Thread-Release-IWI-DDS-Fast-Converter-V1-40.html
side note: you need winwar or 7zip i use winwar so this guide will be with winwar.
Step 1
Make a folder with all the tools and then extract the tools.
now all you have to do is install paint .net.
step 2
To get the textures you are going to want to open GreyHound, then you are going to want to settings and check the boxes.
now you want to open the game you want the textures from (in my case black ops 2) once your game is open load into a map of your choice, once you are in a map go to grayhound again and click load game.
now you find the texture you want in my case it's weapons then you export them.
now you want to go to the folder you installed grayhound in and look for a folder called exported files in there you will have all the files you exported includeding textures let me show you.
step 3
This is where the fun begins, take those textures you just exported and open them in paint .net then you can design your skin/camo.
When you are done save the file as a DDS file then take it to the IWI/DDS converter and make sure you type the right number for the game you want.
step 4
To install your skin on pluto t6 go to your C:\Users(your windows user)\AppData\Local\Plutonium\storage\t6\images and drag your IWI folder in the images folder if you don't have one make one let me show you me testing my example camo.!
If you guys need leave a comment and i will get back to you when i am not busy for now have a great day i hope this helps.