Important! I don't really know anything about modding this game! I used Wiki and all this info is basically a bit more compact and poorly explained version of it's guides with tiny additions!

• Download "extract-rise-pak.bat"  here and unpack and put it in a separate folder
• Open MH Rise installation folder, find file named"re_chunk_000.pak" and drag it onto the bat file you downloaded
• It will download the most recent .list file, containing a list of all the files from the pak and RE Tool and start extracting the contents of .pak file
• OPTIONAL When it'll start extracting .pak file you can stop it by pressing CTRL+C . At this point you can open .list file with text editor of your choice and erase all the stuff you dont need. E.g if you want to extract all the armor you can erase all the lines that do start with "natives/STM/player/mod/". More detail here
• Now drag "re_chunk_000.pak.patch_001.pak" file onto the bat file. At this point you'll have two folders named "re_chunk_000.pak" and "re_chunk_000.pak.patch_001.pak", just overwrite first folder's content with second one's
• Locate the folder with armor you need at natives/STM/player/mod/ (f for female armor and m for male) /pl (armor ID)
  and copy it's contents into a separate folder and rename the files accordingly
• To add your mod into Fluffy you have to create a proper folder structure (Name of the mod)/natives/STM/player/mod/ (f for female armor and m for male) /pl (armor ID)/ (your files here)and create a file named modinfo.ini  in mod's root folder (you can just create a .txt file and rename it) and put mod description in the following format 
  name=My Mod
version=v1.0
description=What mod does duh
author=Your name here
category=Category
category=SecondCategory
homepage=
screenshot=preview.png

  Don't know if any of it is actually required, so you can skip most of it, but you don't want to leave your mod without a name at the very least
  
  Now just drop that folder into Fluffy Mod Manager\Games\MHRISE\Mods or archive it and drag into the Fluffy and activate it
  
  To add a preview just drop a picture into mod's root folder and add screenshot=(file name) into modinfo.ini file