Drop the file in your mods folder, you'll need mod engine installed in your game base folder, you may find one in Dark Souls II Scrambler - Randomiser(https://www.nexusmods.com/darksouls2/mods/1163). Or you could use Load Loose Param Files(https://www.nexusmods.com/darksouls2/mods/1092) After that you should drop the file in my mod to param folder located in wherever you decide to install you param files. It may looks like these: X:\Dark Souls II Scholar of the First Sin\your mods installing folder\Param X:\Dark Souls II Scholar of the First Sin\\Param